Another big + for the 360 IMO is the fact that you can go to a Target or Walmart and pick up a 13 month subscription to Xbox Live Gold with out having to give a credit card # online just get the card from the store and put in the redemption code.
This is exactly what I did. I bought mine from Best Buy. I've read a lot of horror stories about Microsoft's practices about storing credit card information and not doing the best they can to keep it private. If you give them a credit card number online, and at a later date you request them to remove it from their database, they will not