I just finished the update.  No problems here.  Prior to updating, I did backup my data as well.

It does stink that BBM 5.0 will not work.  Hopefully, Verizon will release a new update soon that will include the fully unlocked GPS and capability to upgrade to BBM 5.0 as well.

As for the plug icon not showing up while connected via USB, it may be a problem on your own PC.  I had the same issue a while back and Windows was saying did not recognize connected device.  I have read other people had similar problems with a various level of successful troubleshooting.

1) Try a different USB cable.

2) Uninstall the drivers through the device manager.  Reconnect and let reinstall.

3) To narrow down that the problem was with my BB device, I ended up connecting to a different computer as well as trying someone else's blackberry.  I ended up going to VZW Store and they replaced my curve as it was under warranty.  Even their machine was unable to connect to the port.  Fortunately when that happened, my Bluetooth connection worked and I was able to back up everything then as well.