1. For 5D2, if you save images in jpeg (any size), and if you use fast CF card (known as UMDA card), if you hold down the shutter button, the camera will take 3.9 photos every second, until the card is full.
If you save images in raw, the camera will need to pause to catch up with saving the files to the card.
2. For 7D, yes, it can take 126 jpeg or 15 raw, then the camera will need to pause for saving to catch up. I have not tested this as to how long it will pause. I save action photos in jpeg, and have not yet hit the 126 ceiling (that corresponds 15 seconds of continuous shooting which is very long time!)
