For the current 2009 model year, these (in alpha order by brand) are the direct drive ski boats available:

Centurion - T5
Correct Craft - Ski Nautique 196, 206, and 216
Gekko - GTO 22 and GTR 22
Malibu - Response LXI and FXI
Mastercraft - Prostar 190, 197, 214
Moomba - Outback and Mobius LS
Sanger - D215, DXII, and DLX
Ski Supreme - 220SP
Tige - 20i and 22i

Since the 2007 model year, Ski Pro appears to be out of business, and both Supra and SVFARA brands no longer offer direct drive models.

Of all boats on the market, only a handful have successfully met the evaluation for water ski towboats and been approved to pull sanctioned events. They are:

Correct Craft - Ski Nautique 196 and 206
Malibu - Response LXI and FXI
Mastercraft - Prostar 190, 197, and 214
Moomba - Outback

Our Outbacks are indeed special.

The weather today is rainy, so I found myself leafing through the 2007 Boat Buyers Guide that helped us make the decision to go with Moomba. When we compared everything that was new on the market at that time to what we wanted and could afford, hands down it was a Moomba.