Good find. The Parrot Smart actually makes a go at using only Android and comes from a more known/respected company than the other "Android" headunits showing up on the market.
However, the Smart is the equivalent of sticking your 2-3 generation old Android phone in the dash with a larger screen and an audio amplifier. Personally, I think I would try my hand custom mounting a tablet (ex: Nexus 7).
It may work for you, but the lack of RAM and OS/app storage would be problems for me. My email for example would eat up a good portion of the 1GB storage. I suffered through that before upgrading my Sprint Evo 4G to a Samsung Galaxy S3 a year ago.
Parrot Asteroid Smart Review: Android In Your Car's Dash? - Android In Your Dash Via Parrot's Asteroid Smart
Easy to side load apps
You can root the device
Doesn't treat Android as gimick (see dual OS units)
Capacitive touch display! (biggest problem in my book with the other "Android" head units on the market)
Price point is reasonable
Android 2.3 (it will work for now, but will apps stop supporting this old version in the future?)
2005 era CPU (same as Droid 2 or Droid X)
1GB storage for the OS and apps
Not that good at traditional car audio (doesn't resume playback, no native XM/Sirrus, works just okay with USB/SD card based music storage)
May have issue with OBDII Bluetooth adapters
Overall, it looks like a fairly well implemented unit, but compromised by the old HW and to a lesser extent older Android version. Using a better CPU/SoC would add some costs, but would be worth it for a buyer who expects "modern" Android running in the car's dash.