Schumi behind the wheel is an unknown combination... especially with Schumi at age 41. Massa is not a known talent at this time due to the accident. And, Button is known to be good with a fast car but we don't know how the McLaren will shape up and how Button will fit in with the team. This leaves the real challengers, in my guess at the WDC order, to the championship being the following (IF the cars they drive fast and reliable cars with solid teams behind them): Hamilton (truly one of the best talents to ever sit in an F1 car), Alonso (IF he can get his ego act together), Vettel (great driver with incredible potential and a good team), followed by whomever from the "questionables" above. While the actual tech rules for the cars have changed a bit, it is a possible safe bet that those who excelled at the end of 2009 will be the ones to watch for 2010. Each team may or may not have a completely new car from the ground up, but with the new fuel load rule, all bets (even my guess for the WDC order) are off due to any modified aero or wheel/suspension loading due to the new fuel load rules. Certainly, strategies will be drastically different than ever before. It will be an interesting season to watch, with Todt and the FIA being an additional unknown factor... favoritism continuing to rear its ugly head (ala' Max), hands off, or consistent rulings? No one really knows. Testing may give some clues, but will they be only showing teams experimenting or we see accurate representations of the real thing?
Although the tyre issue may be important this year, we still don't know how much. This is no 2005, when drivers couldn't change tyres in a GP and Schumacher had a lot of really bad races by still doing the kind of thing he has always done on previous years (fast tyre-thrashing laps before a nicely timed pit stop to be back on track in front of the competitors). It's all about the kind of tyres that Bridgestone will deliver. If they're hard enough so that drivers won't do much damage to them even when they carry a ton of fuel, than it won't make any difference. And we know that, since Bridgestone became the sole tyre provider, tyres are much harder than in previous years, so the odds are still favouring those which are not very kind on their tyres. I just hope it happens otherwise, it would be fun to see some competition at McLaren and Mercedes... Also, that would mean that the guys which are hard on tyres may have a worse first stint than the others, and perhaps their performance would be reversed at the later stages. Which could mean more overtaking moves, at last.