The Sony "T" series of cameras is an evolution starting with the T100.
There was the T100, T200, T300 which came out 6 months apart.
Then in Aug of 2008 Sony introduced the T500, T700 and T77.
The T series of camera switched to a touch screen LCD with the T200.
The T500 is an evolution of the T100.
The T700 and T77 introduces a thinner camera with a zoom lens of only 4x (instead of 5X).
So you can not assume the T700/T77 will work just like the T100-T500 series of cameras since it uses a different lens.
The T700/T77 are much the same.
The T77 is the little brother of the T700.
It has a smaller LCD (3.0 inch) and less internal memory storage.
Here is a comparison of specifications:
I have not seen a review of the T700 or T77.
Cnet gave the T100 an Editor's Choice Rating. They haven's reviewed the T77 yet. Is the T77 the newer model of the T100? Are there any reviews available? Has anyone had experience with both cameras or even with just the T77?