For any new parents out there...
http://www.4moms.com/mamaroo
this thing has been awesome for us, and our kid freaking loves it. We don't just leave her in it though... we do try to actually rock her every now and then too, but it's nice to have when you just need a couple seconds to put the baby down. You can also connect your iphone / ipod to it and it'll play the music off your device.