I have a 360 and a Wii personally, and I really like my xbox 360.
It think you should get the PS3. You have an HDTV, and you are going to want to play Blu Ray movies, since you are concerned about utilizing your TV. PS3 is a reliable console- its also the sturdiest of the 3. PS3 doesn't have as many good games as the 360, but it has enough. More importantly, you can play with your friends. I refuse to pay for online and think pay to play online sucks. PSN is free.
I am a huge fan of Banjo Kazooie and my friends have 360 and it was cheaper and it had more games I wanted, but they are both great consoles and I considered getting a PS3. I think in your case PS3 is the better choice.
You need to buy the HDMI cables seperatly. PS3 comes with composite cables only :(