In no way do I see a resemblance to Apple/Mac, so I’m not sure where that came from. I think the new logo is actually a Window and not a flag anymore. The perspective hints at the fluidity and movement that is now a key experience in the Metro UI. I’m not sure why they went with that blue, or if it’s flexible in use in terms of color (I would assume yes). I’ve seen reactions go both ways, but at the end of the day I feel like it’s not amazing and it’s not offensive. It lands it the middle and I’m ok with that. I feel like Microsoft as a comapny, Windows as a product is already so big and recognizable in any form that it wouldn’t really suffer or gain from this redesign, but I understand their desire for something fresh for what is “a new era” of OSs.
Here’s some pieces to read on the redesign, one from MS, one from pentagram (the firm who did the work).