Animal Magic (11/6/2012)
Check out Adam Machanic's WhoIsActive procedure. Its fantastic for this sort of thing and comes with excellent documentation on multiple uses of ithttp://sqlblog.com/blogs/adam_machanic/archive/2012/03/22/released-who-is-active-v11-11.aspx
Hope there isn't any issues with linking it here. If there is then feel free to delete the post mods.
We use that as well and it is a very handy SP. The advantage of the sp_blocked_process_report_viewer is that it gives the the actual blocked process chain with the lead blocker at the top of the chain and the XML output to determine what is causing the blocking. We've customized the original version of the stored procedure to parse out the PAGE and OBJECT data as well so you can easily determine what is being locked that is causing the blocking to occur.