Xbox Live 2 month free question

[nelsed]

OK, so I just signed up for this deal -- and it's nice to be able to try it out.. but I also have another valid ID with another game I bought... etc.. how long can you keep switching between these and get another 2 months free if at all???

Do they track your name, address or credit card???
do you have to switch your callsign online or what?

Thanks for the help

[MrJeff]

I'd look at the terms/conditions of the key. I was wondering the same thing though, but I don't even have my xbox yet. Anyone?

My guess is that you can't stack them as people give them away pretty freely on here and other boards.