Exact same problem at http://www.fishwrench.com — running WP 3.1 and buddypress 1.2.8. Also running buddypress forum extras v0.3.0 and 1.3.2 of the buddypress activity stream.
This is probably unrelated, but the following line is throwing an invalid character error in IE8: $(#signup-welcome).p(;:last-child’).css(‘display’, ‘none’);
ERROR:
Webpage error details
User Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; .NET4.0C; .NET4.0E)
Timestamp: Wed, 30 Mar 2011 04:37:56 UTC