The best one I have found is WP-FB auto connect.
I’d say try WordPress plugin “social login, social sharing and social commenting”. You can disable sharing and commenting if you do not want them. Here is the link – http://wordpress.org/extend/plugins/loginradius-for-wordpress/
As @sheffieldlad suggests, wp-fb-autoconnect delivers a good off the shelf solution, and provides some integration with BuddyPress profile fields
[ note: wp-fb-autoconnect is a facebook only solution, and everything is installed / controlled on your site; Pro version is a one off payment. Loginradius is a SaaS solution, with monthly payment plans to enable full features, remove labelling, etc. If you want a full SaaS solution, you should also look at Janrain, Gigya and Oneall. ]
anyone tried the addthis social signin with buddypress yet? does FB Twitter and G+. i use their link sharing plugin and was planning to try out the new signin plugin asap:
http://www.addthis.com/blog/2012/11/20/introducing-social-sign-in-for-wordpress/
@ubernaut haven’t tried it yet. Let us know if it works out all right 
@mercime — oa-social-login is from the company I referenced: One All
As with the others, there is a free version, but you have to pay monthly subscriptions for their service if you want more features, users, etc.
Thank you @rogercoathup Good to know for future reference.
@mercime i will try but i might not test this for a little while yet.
@ubernaut Thanks. No worries, I’m handling private BP sites at this time 
Thank you for this great info.
I am also looking for a free open source plugin for social login and connecting etc.
The paid ones are too much to afford at this time.
I will research these two a bit more:
http://wordpress.org/extend/plugins/wp-fb-autoconnect/
http://www.addthis.com/blog/2012/11/20/introducing-social-sign-in-for-wordpress/#.ULVOnOTO3n4
Btw, WP-FB-Connect is a free plugin for WP and BP but it is paid if for Multisite (single license $30, Developer license $70)
Still trying to find out more details about the http://wordpress.org/extend/plugins/addthis-social-sign-in/
@rickkumar – I noticed loginradius have been spamming the Internet with fake users / testimonials for their product — so probably good to avoid that one.
If you are looking for another free solution – you can investigate HybridAuth. That one’s a PHP library, rather than a plugin, so you’d have to do some coding, but on the positive side would gain a lot more flexibility.
Thank you @rogercoathup Good to know for future reference when I need this functionality in few weeks.
I just checked http://hybridauth.sourceforge.net/ and it looks very powerful and free.
Is there any Multisite/BP plugin already available for this?
Btw, here is the latest about “Social Sign In” using Facebook/Twitter/Google (linkedIn soon) plugin from addthis.com guys:
http://wordpress.org/extend/plugins/addthis-social-sign-in/
I asked them few questions as follows on there site:
http://www.addthis.com/blog/2012/11/20/introducing-social-sign-in-for-wordpress/#.ULahMuTO3n4
My Questions:
Is this for ‘social sign in’ only?
Any plans to eventually include social sharing and social commenting?
What kind of cost if any are we looking at?
Does this plugin supports all the following:
1. WP
2. WP MultiSite
3. BuddyPress
Please advise.
Thanks.
AddThis.com answers:
Matthew Keesan on November 28, 2012 at 10:00 am said:
@RK
1. It’s only Social Sign In. We have a host of other plugins however for some of these tasks. We decided to keep them separate to give you maximum flexibility.
– Social sharing: http://wordpress.org/extend/plugins/addthis
– Following: http://wordpress.org/extend/plugins/addthis-follow
– Welcoming: http://wordpress.org/extend/plugins/addthis-welcome
2. It’ll always be free! Since we’re just a middleman there’s no significant cost to us providing this service, so we’re happy to pass the savings on to you!
3. We haven’t tested on Multisite or BuddyPress yet. If you do, I’d love to know what happens.
—————————————————
Note: I don’t have a live site yet.I am wondering if someone can test it for Multisite and Buddypress?
Ok, found two plugins for ‘wordpress’ based on HybridAuth:
http://wordpress.org/extend/plugins/socialauth-wp/
http://wordpress.org/extend/plugins/wordpress-social-login/
Q: Does any of these two plugins work with Multisite and BP?
Thank you.
There’s a premium facebook plugin which works with BP and mulitiste for sites I’ve handled http://buddydev.com/plugins/buddypress-facebook-connect-plus/
Having said that, http://wordpress.org/extend/plugins/socialauth-wp/ looks good as I see that the plugin dev is active in supporting the plugin. I don’t think the plugin provides support for BP as the plugin dev would have added the BuddyPress to the plugin tags. Best place to ask is at plugin’s forums http://wordpress.org/support/plugin/socialauth-wp
I just asked in the SocialAuth plugin forum if they can make it compatible with Multisite and BuddyPres.
http://wordpress.org/support/topic/does-this-plugin-work-with-multisite-and-buddypress-1?replies=1
Hi all and thanks for all the info 
I’m looking aswell for a plugin that automatically fill in the Buddypress users’ X-Profile data from the uers’ Facebook profiles.
I have tried the free version of http://wordpress.org/extend/plugins/wp-fb-autoconnect/ but it has a serious problem. If I login with my FB account a few times, this plugin create a new user every time in the wp_users table. I don’t know if the premium version of this plugin fix this problem, so if any of you have tested it, I would be very thankful for your comments
Meanwhile, I’ve tested the BP demo of this one /loginradius-for-wordpress/ and it doesn’t duplicate the user. But I prefer not to use a external service.
So, I found this one buddydev.com/plugins/buddypress-facebook-connect-plus/ (thanks to @mercime) and it looks perfect for what I’m looking for. Any of you have used it? if you do, does it duplicate the same FB user in wp_users? and does it work fine importing users Facebook data to BuddyPress profile?
Thank you very much for your help and if I find more usefull info about this, I will post it here
Unfortunately none of these really stand out for a Facebook/Google/Twitter option:
BuddyPress compatible
LoginRadius – External service. Customizing registration page requires $49/mo. option.
WP-FB-AutoConnect – Facebook only. Creates duplicate users?
BuddyPress Facebook Connect+ – Facebook only. $30 (3-months) to $99 (year) to update plugin.
OneAll Social Login – Not customizable. Free up to 2500 users.
Not designed to be BuddyPress compatible
SocialAuth-WordPress
WordPress Social Login
AddThis Social Sign In
What does it mean to be BuddyPress compatible anyway? Why is it that the best plugins, SocialAuth-WordPress, WordPress Social Login, AddThis Social Sign In aren’t ‘BuddyPress optimized’?
I’m having a developer implement one of these for our site, and I’d be glad to share what we needed to do to ensure that we have a registration form with a few required fields, and existing users can use this service as well.
From WordPress forum:
http://wordpress.org/support/topic/does-this-work-with-existing-registered-buddypress-users?replies=8#post-3783207
“so i have not encountered any problems with wsl with bp and if there is its pretty much manageable via the settings. but it would be epic if wsl will be officially be compatible with bp.”
My developer is trying to use Nextend Connect, separate plugins each for Facebook, Twitter, Google. Anyone try them? I’m not sure the individual ratings are real, but they’re pretty glowing: http://wordpress.org/extend/plugins/search.php?q=nextend+connect
