Bob,
While you are moving up to the A700, you just might want to consider dropping a few extra dollars to improve the glass you are currently using to get the most out of the A700 body.
Now, I realize that this is unsolicited ... so just bear with me, here. I also know that people are not made of money and I am also not suggesting
Carl Zeiss-glass (which is great stuff, but most folks can do quite well without having to make that leap). What I am suggesting is a couple of lenses that will give you snap in your images (focus-wise and image-quality).
Number one improvement plan -> Quit using the "kit" lens. It just does nothing useful for most images and you can do so much better with almost anything else. When you buy the replacement, just kind of lose this one.
My personal favorite, which is reasonably priced, is the
TAMRON SP AF 17-50mm f/2.8 XR Di-II LD Aspherical (IF). This lens will literally change the way you see things. It will come back, on the A700, with some of the sharpest images you will have shot. It also give you a "fighting" chance with indoor shots, while not using a flash.
An alternative, if having the wider aspect is not important to you, is the
TAMRON SP AF 28-75mm f/2.8 XR Di LD Aspherical (IF), which is the "Full Frame" equivalent on the A900 camera. It is priced slightly cheaper than the 17-50, but gives you a little more telephoto range.
The last last is a real budget saver and provides superior
Image Quality for the price, and that is the
TAMRON SP AF 70-200mm f/2.8 Di LD MACRO (IF). With either one of the first two and this last one in your bag ... you should not have to worry about sharpness, again ... like forever!
I have a feeling you are not quite happy with what you have been getting out of the A100 and are figuring the A700 is the logical solution. To be honest ... its probably your current glass. You are working with the roughest edge of digital optics ... and they just aren't quite up to the task. In fact, I would say you need to try and locate the lenses I listed, above, first, and mount them on your A100.
Do a "trial" or evaluation shoot. Take the dog with. Shoot your subject (the dog, perhaps) with your current lenses and, using the same settings (write them down), then switch immediately to the f/2.8 TAMRONs and shoot again. Examine the results on your PC monitor.
If I'm wrong about this, I will be amazed. Before you sink the cash into the new camera body, why not see what kind of mileage is left in ol' Betsy (A100) with a pair of really nice lenses. Remember: No matter how good a camera body is ... it cannot improve your glass.
Good luck.