Is anyone doing this?
In Europe, this is becoming more and more common. Towing works
astonishingly well with 100 hp and one of those new planes. The limit is
when the glider is very heavy (fully loaded two seater) or the runway is
very short and soft. Towing with 3 gal/hour and with remarkably little
noise is much cheaper and neighbour-friendlier, even if a tow it last
10% longer.
There are currently two categories of "new tow planes": Motorgliders
(such as the Super Dimona, in the USA called Katana XTreme) and modern
ultalights, as they are called here (see for example
http://www.remos.com/).
All in all, in Europe we strongly believe that this is the future of towing.
Stefan