I don't know of a specific thread for the 360 version itself, but you can still discuss the 360/PS3 version of the game in the 08 sections if you like
To discuss ideas for future versions you can go to the
wishlist section.
If you want to see how many people would be interested in an online league you can make a post in the
general section.
If you make a league and want to announce it, you can post it on the
community switchboard.
If you want to talk about customizing the 360 version, you can talk about it in the
general section and if you release any rosters or have any game settings you would like to offer you can make a thread in the
releases and previews section.