Is it really that GM has failed to innovate? Let's look at the numbers:
GM======================================Toyota
$1,525 in healthcare per vehicle $201 in healcare per vehicle
$73.73 avg cost of a labor hour $48 avg cost of a labor hour
34.3 hours to build a vehicle 27.9 hours to build a vehicle
Loses $2,331 per vehicle Makes $1,488 per vehicle
So, let's just alter GM's healthcare and labor costs to Toyota's levels. Lowering labor costs would save GM $882.54 per vehicle. Add to that the difference in healthcare costs and GM would save $2206.54 per vehicle - nearly making them profitable right there! Yes, they're still not profitable, but it would be a huge difference.
The other things they need to do is use less labor hours to build a vehicle, increase plant utilization (which is only at 85% right now), and get idle workers off their payroll - yes GM is contractually obligated to pay people not to work.
GM should innovate. They do need to come up with better models. They do need more reliable cars. They do need to be more fuel efficient. However, none of those are really their big problem. GM is still selling nearly as many cars as Toyota. They don't have problems creating popular cars. That's a misconception with many people who happen to dislike GM cars (heck, I think they're complete crap).
The big question is, can GM reduce those labor and healthcare costs? If not, they will NEVER, EVER be profitable. You can't compete with a $2,200 handicap per vehicle. In fact, it's a testament to GM that they have been able to compete for so long with such a huge disadvantage. If those costs can be lowered, GM just needs a small loan (like $25bn) and a few years time. If those costs can't be lowered, we'll be talking about giving them another $50bn in a year and another $100bn in two years.
EDIT: Figures provided by NPR (http://www.npr.org/news/specials/gmvstoyota/)