I actually live in a very populated area with a strong Verizon network and I'm having similar issues (i.e. when calling from my house my signal fluctuates from full bars to zero-one, which causes my voice to cut out). I spoke w/VZW tech support and was told that it's a hit and miss issue with the software. In other words, some units have the problem and some don't. The new software upgrade is slated to roll out next month, which they believe will fix most, if not all, the "quirks" people have been experiencing.
The other solution was to do a hard reset, which essentially entails returning ALL settings to default. This will also remove any personal customization and contacts...no thanks. It also has to be done over the air, while a VZW or HTC (can't remember which) techie walks you through the process. My Eris is working great (no battery issues), and this isn't a chronic problem for me, so I'm waiting for the SW upgrade. Good luck!
