Updating to CWRecovery 3.x is only needed for certain renditions of the CM7 nightly rom builds and/or the accompanying 'gapps' file. AFAIK, CWRecovery 3.x is not really a supported recovery, but just as 'beta' as a CyanogenMod Nightly rom build. This is just from what I've read.
And judging from what I've read about it and the several problems some have had with it, I'll just wait and see if it comes to rom manager and then go from there unless for some reason I REALLY need to have it.
If you _really_ want to try out a new recovery, try out the RZRecovery.