Next to your name, It will Show the level/rank/prestige sign
Yes, you can level up online just like for the xbox 360, ps3 and computer. I know this for call of duty 4 and 5 for the wii but have never played call of duty 3 or prequals so don't know about them.
no but i know that someone got go level 62
It will show your prestige emblem and your level right next to your gamertag.
become a colonel which level i do not know.
In Call of Duty 4: Modern Warfare, the M14 rifle is unlocked at Level 46 in multiplayer.
play day and nyt
level 70...10th prestige
there are no ghosts
Next to your Gamertag or PSN name on the Multiplayer menu there should be an emblem with a number next to it.
Level 10
Level 25
You unlock it at level 57.