3 > 4 ... Good move
Got my iPad 4...3 is up for sale. Got a gift card for staying with Verizon FIOS which was unrelated to this, that should make up a lot of the difference. I am a very heavy user both at work and at home, so am used to the 3 speed. I noticed the speed difference immediately. I have a very fast WIFI and saw the difference as people have said browsing right away. LTE is quicker of course as well. The main reason for the upgrade though was that I have a photography side business and as part of my workflow, immediately import my 28MB raw photos into the iPad. It takes forever on my iPad 3, but gives me some security should my SD card go bad ...always have your photos in two places...photo gospel. I will take a bunch of photos over Thanksgiving and post up feelings on speed both in upload and in iPhoto performance. I am hoping for a bigger difference than less hefty CPU/GPU chores.
You know what though, that's a great rationalization, but I absolutely love the snap I am getting just doing normal things. I know, read all the crap about it not making a big difference, but I am seeing it. Good choice if you can get away with a good resale and don't have to spend a lot on the upgrade.