My TV will only do 1080p over HDMI (which I'm currently doing via a HDMI cable - no problems there). However, I want the ability to plug some headphones into the 360 so I don't keep the wife awake if I game late. I've just realised that I can't plug the component adapter and the HDMI in at the same time - they don't fit 
Question is therefore, am I really missing out by gaming @ 720 instead of 1080? This is all taking place on a 42" screen. The question is also relevant to a smaller monitor, as I am planning to get a 20/22/24" at some point so need to decide between 1920*1200 (for 1080) or 1680*1050 (for 720).

Question is therefore, am I really missing out by gaming @ 720 instead of 1080? This is all taking place on a 42" screen. The question is also relevant to a smaller monitor, as I am planning to get a 20/22/24" at some point so need to decide between 1920*1200 (for 1080) or 1680*1050 (for 720).