It took a bit of effort for me to obtain my Apple iPad 2 last March and I use it just about every day. I had the first iPad and probably could have been just fine sticking with it, but I wanted the new form factor, processor, and integrated 3G. The only thing I have ever thought could be improved, particularly when reading ebooks, is the display on my iPad 2. It's pretty certain that the iPad 3 will have a higher resolution display, but that is not enough for me to upgrade again (at least that is what I say now).
There is quite a bit of information from different sources prior to the 7 March announcement, which is a bit unusual for Apple so I am not convinced that all the rumors will come true. The rumored updates include the following:
Display resolution of 2048x1536 pixels (currently the iPad 2 is 1024x768 pixels)
Quad-core Apple A6 processor
4G LTE radio for Verizon and AT&T connectivity
Better front and rear cameras
The improved resolution will be great, gaming will likely be better with the improved processor and/or GPU upgrade, connectivity will be faster, and photos will be better. I usually only play Words with Friends so don't care about the improved processor, I primarily connect via WiFi and when on the road the AT&T 3G works just fine, and I NEVER use the rear camera with the front camera only used about 3 times for test FaceTime chats. Thus, for ME, it doesn't make much sense to buy a new iPad 3. I also paid over $900 for my current 64 GB 3G iPad (there is about a 10% sales tax here in Washington).
The thing about Apple events, and the hope I have, is that they will reveal something amazing and new with the next iPad. If just the rumored updates above are in the next iPad, will you be upgrading?