The software needs some time to adjust, at least a few hours. Usually your iPad will work better after one or two days.
Perform a reset, if you haven't done so yet. This won't remove data or change settings, it might help a bit with your iPad's performance. Press and hold Home and Power button until the Apple logo appears. Then let go of both. Your device will power up on it's own.
If you updated over the air (Settings - General - Software Update), restoring via iTunes might help as well. This will remove everything from your device completely and install a fresh version of the new software. Make sure you have a most rcent backup to restore from afterwards.
Another reset might be useful after restoring.
Hope that helps.