Well I got tired of waiting for a decent holster style case to show up for my Pre. I tried the OEM leather case for the blackberry 8300, and it fits the Pre really well. It holds in, and the the magnetic strap that covers the top keeps the pre safely inside even if the holster goes upside down. You can reach the volume buttons too from the side when the Pre is in the case.

The holster swivels on the belt too, and feels good. And it's available pretty much everywhere Fry's (where I got it), best buy, etc...

For $16 it seems to work well. I feel the vibrate just fine when it's in the case too.

You do have to pull it out of the holster to use it, but that's fine with me.