Games : What's up with the "new" 3ds?

A few questions about the "new" 3ds:

1: Is it worth buying when I already have the 3ds?

2: How much better is the "more stable" 3d and how is it more stable?

3: What does the ZL, ZR, and C-Pad do? Are they there to help out or (read Q4)

4: Are there going to be games exclusive to the "new" 3ds? (Due to the new buttons)

5: How hard is the "new" 3ds's cover?

6: Where can I get one for cheap? 7: Is the XL version any different than regular expect for size?