In AnandTech's article on Apple’s 45nm Refresh: New MacBook & MacBook Pro, I found a statement extremely interesting:
The Mobile GM45/47 chipsets are an integral part of Montevina and will feature the new GMA X4500HD graphics core. The X4500HD will add full hardware H.264 decode acceleration, so Apple could begin shipping MacBook Pros with Blu-ray drives after the Montevina upgrade without them being a futile addition. With full hardware H.264 decode acceleration your CPU.
Could Apple be waiting on a refreshed hardware platform from Intel before releasing HD movie downloads from iTunes to computers with this stuff? When H.264 encode/decode goes off-CPU for all computers, then the battery drain while be manageable. I might hold off purchasing a new Mac until this happens.