new macbook battery issues

Hey,
I'm sure there's another thread about this, but I can't find one...
I have the new 15 inch i5 2.4 ghz mbp...
I calibrated my battery a week or so ago...after that was done I had 7 hours (usually)...I thought that it was a little low but it was fine..

Now, a week later...my battery only ever charges (even when I charge it completely and leave it for an hour without touching it) to 5 hours...and its declining rapidly...every time I charge it, it seems like the remaining time limit drops 20 minutes or so.
Has anyone else experienced this? What is going on?

Thanks