Cute ad. Flawed, but cute.
Let's take one thing at a time.
1. Windows 7 doesn't come with BR support, you have to buy it third party. However, the ad implies that it's natively supported on Windows, so it's misleading and could backfire on MS. There is no reason third parties can't support BR on Mac, there simply isn't enough market for it yet. Slight advantage for Windows.
2. The "bag of hurt" Steve Jobs referred to 2 years ago was a number of things: the cost of the BR drives, cost and availability of BR source material, licensing costs of BR codecs included in every machine, having a CPU+GPU fast enough to decode 1080p VC1, and compatibility of then available BR drives with recordable DVD&CD media. The cost of drives has come down, and 1080p VC1 decoding is now possible on most new CPU/GPU combinations (although it's still iffy or impossible on Intel IGPs), and there are lots more titles available. However, the licensing costs remain, and media compatibility might still be a factor.
3. For laptops, power consumption is still a factor. Yes, the CPU+GPU may be able to decode AVC or VC1, but will the battery last long enough to play the whole movie? In most cases, the answer is no.
4. Most people won't notice the difference between an upscaled DVD and BR on a 17" or smaller screen.
5. The licensing costs would not raise the cost of Windows by $80+, or even by $50. I don't know the exact BR licensing costs, but you can bet it would raise the cost of Windows by no more than $5. If a third party can sell a BR decoder for $50, you can bet their licensing costs are not more than 10% of that, and probably closer to $1 per copy.
6. It's still questionable whether BR will survive long term. It's certainly looking more likely than it did 2 years ago, but it's by no means certain. There's still a decent chance that streaming video will effectively kill BR before it sells enough to be profitable.
7. I haven't looked lately, but I don't think there are any BR drives thin enough to fit in Apple's laptops. If you think Apple is going to make a thicker laptop just so a BR drive can fit, you're crazy.