I'm reading that iOS 4.3 doesn't have multitouch gestures, and that it might not be available in iOS 5 for original iPad users. But I am confused, I have the multitouch gestures features on 4.3.2, yes my device is jail broken, but no, I've never downloaded a tweak for it. It is in my settings general tab.

So if I were to upgrade to 4.3.3, would I lose the multitouch gestures?

When updating to official 4.3.3 yes but once you jb using redsnow you'll have the option of having them back.

Actually, it matters. If you downloaded it from Cydia, it will go away. If you enabled them in the backup, either with Xcode, or ibackupbot, they will stay.

Honestly I don't remember doing either.