Any speed difference with xcode 3.2.x and 4?

Any speed differences? A friend reported a framerate drop in unity with latest xcode.

XCode makes no difference as it has nothing to do with the resulting outcome but upgrading to the 4.3 SDK on Unity 3.3 can make one or having the device on a different iOS version makes a difference on that end.

So 4.3 SDK is slower?

Xcode 3 and 4 have no speed or build differences whatsoever, it’s really just a different IDE interface.

No 4.3 isn’t slower normally, but it has no interest in ARMV6 anymore so it makes sense to remain on 4.2 if you want to support those 7% or so of the userbase too

Do you guys know if we can keep using Xcode 3 to build IOS projects with Unity 3.3 ?

you sure can.
I just don´t know what happens when iOs 5 is out. Could very well be that thats only inside XCode 4+. And may be they even restrict apps again to something like minimum deploayment target = iOs 4, as they did last time.