Hi, all I have been trying to find out a bit about bitcoins but I still have a few questions:

1. Will mining become increasingly less profitable in the following years ?
2. Assuming you have no power costs then when (if not already) will it become unprofitable to mine?
3. Does the cpu contribute to mining hashes/s or just the graphics card(s) ?
4. If you are managing your own wallet then how do you go about buying and selling bitcoins ? Could you use a site like mtgox?
5. Lets say you install the bitcoin software on a live cd and generate a bunch of addresses, then how do you copy your wallet (where is the file located).
6. What are the predictions for the value of a bitcoin in the following years?
if you can answer any of the questions then your help would be appreciated.
thanks,