We will see a Rebel XS replacement announced in June. I was told the current XS will remain current while the XSi will be discontinued over the summer.
We'll still have 3 Rebels for Christmas. The XS could reach the $400 price point. I still think that's a little unrealistic.
The T1 will not have a movie mode. It'll basically be a rebadged XSi.
Not likely before the fall.