I've got mine setup just about perfect now.
I'm using "tasker" on my phone and tablet, awesome program, it is set so when I leave my wifi zone (home) it automatically turns on bluetooth, kicks the bluetooth teathering in on my phone, and tablet, so the table is "always online" state, bluetooth tethered. Also using Tablet talk to do text messaging (via the cell phone, Galaxy SIII) so my phone almost never leaves my holder.
Then, when I get into the mog, and put the tablet in the mount, there is an NFC tag that fires up my in car program (Car Home Ultra), tethers the bluetooth to the handsfee Jabra Freeway (so at this point, the Bluetooth in the tablet is doing 3 tasks, Internet connectivity via the phone, Text messaging app to the phone, and handsfree, to the Jabra Freeway), sets the messaging volume to maximum, sets the speaker volume to maximum, turns on Vlingo handsfree for voice to text, turns on the GPS chip for location, reads out the current weather, and sets an auto-text reply "I'm driving" so I don't have to worry about texting and driving, and launches my google music app, and starts playing "recent" playlist.
All from just being close proximity to an NFC tag

Android rocks!
Should mention there was just an update for the Nexus 7, it now supports landscape on the home screen, seems little, but big improvement for car mount applications.