Ok, as it seems there are very divided views on the feral DPS class in 4.0.1 I myself have written a guide on the official forums surrounding the changes made to feral in the last patch. You can view it here forums.worldofwarcraft.com/thread.html?topicId=27187856831&sid=1 Feel free to comment and make suggestions and if you have any questions I'm sure that me and the rest of the kitty crew could help to clear things up a bit.
Hopefully this should resolve any issues.
Cheers, Chezburger.