Now if I only knew how to speak Georgian...
You know most Georgians speak English, and most of the signs are in Georgian and English. You can do just fine in Tbilisi with English only. I did. Even a last minute taxi I grabbed to the hotel one day was amazingly efficient, as the man sat there and thought for a moment about what I had said, and then figured out what I was asking.
That said I am going to be learning Georgian.