GM currently sells two hybrids, the Sierra and Silverado hybrids...right now. Here are the plans we know are in the works.
GMT-900's, including Tahoe, Sierra, Avalanche, Escalade, etc, all get new 2 mode system in 2008 and 2009 MY, and following in '10 the Lambda's, including the new Uplander minivan and Outlook and Enclave crossovers will have it.
The Epsilons will all have the new BAS system (G6, Malibu, Aura) as well as the Theta's (Equinox, Vue, etc).
Stuff I'm sure is in the works are the Zetas, G-Bodies (when they are updated), Aveo, Cobalt, etc, with the more expensive products getting the 2 mode, the less expensive ones getting the BAS.
So yeah, they're covering the market even better than Toyota. Toyota isn't going to be able to make a hybrid that will tow ANYTHING because of the way it's designed, while both systems from GM will be able to perform comparably or better than Toyota's Synergy Drive system, while being as versatile as a non-hybrid. Put in to that perspective, I think Toyota's going to be running scared on hybrid production, NOT GM.