Background Skype Drains iPhone Battery .. A lot.

Usually if I start the day with a fully charged battery on my iPhone 4, after moderate home use I have at least 20% left by the time I go to bed. Today I decided to let Skype run in the background because I was expecting some calls. The effect: I had 7% battery life remaining at 1:30 PM!
I plugged it in and charged it to 55%, the left it unplugged, untouched with Skype running again. 2 hours later: 25%! This is a pretty massive problem that renders running Skype in the background basically useless. Is anyone else experiencing this?
