I totally get the idea of waiting until an announcement from Apple. That still could be 2 months down the line if you go by the current rumors. That's just the announcement the actual product may not be out until a few weeks or a month later. Then there is the supply issue. On the current timetable the fanboys will all be there on release date, then with the holiday season everyone will be wanting to get one for Christmas, and there is all the people that waited just for the iPad5. Unless I am lucky, it could take another 2-3 months before anyone has any in stock. I felt I needed to upgrade to a better iPad in the here and now. An iPad 4 will not become unusable the day the iPad 5 is released even though the fanboys and magazine reviewers will make it sound that way. I know that Apple will boost the performance, it's given, but will it be just a bump or will it be a major overhaul. I think the biggest thing right now will be the casing. As for the camera, I don't use a the camera on the iPad, so the camera that is on it is perfectly fine with me as it is. Since owning the iPad 3, - which I got right after release - I can count on one hand how many photos I have taken with the iPad. For photos I mainly use my iPhone 5 or a Nikon DSLR.
I'm not saying I won't have any regrets when the facts of the iPad 5 are announced by Apple. I wanted an iPad where I can get the job done when I needed it done and the iPad 4 with 64GB, WiFi + Cellular was that beast and it is a good upgrade to the iPad 3 that I was using with just 16GB and WiFi.
I rely on my iPad a lot and I wanted to get something that I could use TODAY, not 2-5 months down the line. Under the AT&T Next program that I got this under, after 12 months of payments I can trade in and upgrade to the iPad 5 or by that time even the iPad 6 if I so desire. I am pretty certain that the iPad 4 I just got will last at least the next 12 months.