BuddyPress.org

I have a standard WPMU + BP install going on a dev server, but I’m thinking of changing things around….

What I’m considering doing is having one root domain + multiple sub-domains with their own BP installs. Basically, each sub-domain will be treated like its own island. I haven’t tried it yet, but I’m pretty sure I can share the user table in a database and give each sub-domain install its own db prefix to keep things separate.

Example:
petlovers.com
— dogs.petlovers.com
— cats.petlovers.com
— birds.petlovers.com
— fish.petlovers.com

You can see from the above example that most people would probably only want to see things relevant to their pet type and not be overwhelmed by all the other animal group activities.

Pros
* Once a member registers he won’t have to re-register when visiting a sister sub-domain — though he will have to login again in order to get the site’s cookie. Is there a workaround for this?

Cons
* Members will have to fill in their profile details for each site. I believe that’s the case… unless that can be shared, too?
* A member’s Friends and Activity will only be logged for that sub-domain and won’t aggregate itself sitewide (good and bad)
* Each sub-domain would have to be upgraded separately. (Drupal has a way of using a single code base for multiple domains and sub-domains. Is that even possible with WPMU + BP?)

I’m open to your thoughts and advice on this setup or a different strategy to accomplish the same thing.