Thanks a bunch for providing the numbers Greg!
Yes, they seem light, but why are people surprised exactly? They thought that BMW was going to ship a $65k car with optional forged wheels that weigh 30lbs? I don't think so. The BBS wheels are 20-22lbs so 23-26lbs for the OEM wheels are totally reasonable.
Now that we know the tires + wheels weigh, we'll just need to be patient until someone weighs the tires alone. I'd say the error margin on the tires might be more like +/- 1 lbs, but not more than that. You'd figure Michelin would know how to weigh its product.