Jut found this about 30 min ago
http://www.youtube.com/watch?v=HMijuc5qX7M
judge for yourself.. the 4 is indeed a little faster according to the video but not by leaps and bounds.. Maybe a refurb 3 would be ideal to hold me over until the 5 comes out
If you skip to the end, you will see that he is having WiFi issues on his iPad 4. He got 4Mbps on his iPad 3 and 1.8Mbps on his iPad 4. Such Internet speeds will serve as a bottleneck in web pages and other network-enabled apps.
With my Asus RT-N66U router, the iPad 4 produces Speedtest results of 80-85Mbps with my FiOS Service (and 92Mbps when transferring files over the network). My iPad 3 maxes out at 35-40Mbps. My browsing experience, at least with my Internet connection and router, is very different from that shown in the video. Most sites load noticeably faster on the iPad 4. Other sites load the same (instantly) on both, but then the iPad 3 hangs for 0.5-2.0 seconds before I can do anything; there's no hang on the iPad 4.
As I stated before, I think Internet connection speed should be one factor (among many) in the decision of the iPad 4. If you only have 5Mbps Internet service, I suspect you will be constrained on most Internet sites by your Internet connection speed, rather than the processor on the iPad 3. Based on my router's performance monitoring graph, most web sites will load in the 40-50Mbps range if you have the ISP to support it.