I think they are better off keeping it for BTO. They can keep the entry price lower and if you want some other drive, you might as well put it in yourself and save some cash. I also think 7200rpm drives are a bit harder on the battery and probably have a higher fail rate (just guessing, the faster something spins the larger the force become).
Bottom line, Apple can't create the best possible laptop and keep the price down and their margin up. Honestly, most people that buy a MBP are not pro and probably don't really care about performance as long as it gets stuff done. Still a great laptop but you know, no USB3, no bluray...
Then people are being taken for a ride. At least for the higher-end MBPs. And I don't mean lack of USB3, blu-ray, etc. They would be nice to have, but those aren't the reasons. Especially for a high end 17" model that is clearly aimed at content-creation, since people that don't care about performance will not ever shell out $2500 for a high-end laptop.
I also disagree that the MBP is the "best possible" laptop, though I wish it was THE best possible laptop (thanks to OS X, which - you bet - is the better OS): Unless the cost of the battery is so extensively high that there is no option than to undercut elsewhere (RAM, etc), then they are cutting corners deliberately to pocket the difference, if not trying to coyly say how people don't need the higher-oompf components.
Not to mention how the 2011 17" model's 90W power supply gets blisteringly hot when the laptop runs on it, and that's due to the supply's wattage being too LOW. (it's also why the 17" lasts far longer on battery than the 15" - because of the raw battery size). Here's a real review that did power tests for the 17" model, and the results are interesting:
http://www.notebookcheck.net/Review...-GHz-quad-core-glare-type-screen.50346.0.html
I hope the late-2011, 2.4GHz revamp with faster GPU does have a larger battery and more capable power supply. Otherwise the extra speed will be pointless - for the same reason the early-2011 model doesn't. (I wouldn't have bought the 2.3GHz version, knowing that information...))
It does not cost much more to throw in a 7200RPM laptop.
It costs $60 more to upgrade to 8GB RAM. It's not green for a person to buy a $2500 laptop just to replace the RAM and let two 2GB modules gather dust.
Is profit so much an issue that Apple will not be a little kinder toward those shelling top dollar for purportedly production-grade specs at a price that is definitely the sort that only a professional would spend money on?
As for battery life:
http://techreport.com/articles.x/17010/13
There are a lot of interesting differences, some are in the 5400's favor I will admit. Still, boot times are better with 7200RPM, as is video editing (if people do that on a laptop, but the 17" is worthy as a desktop-replacement...) For this I'm now ambivalent, but I do think it is about cost-cutting more than anything else that they stick with 5400RPM.