I think people have certain expectations about what to expect from an OS thesedays.
They see OS X or Ubuntu and all the great app's that come with it and think that they'll be getting something similar with windows... and assume there are 'no new features' because there isn't an office suite or 'creativity' suite.
I don't think Windows will ever provide those things, but i think people are beginning to expect an OS to come with a certain degree of productivity/functionality out of the box - notepad, movie maker beta or that very basic photo live thing.
Because windows is so popular, they'd likely be accused of anti-competition if they did as the market for pro-sumer level applications on Windows is mammoth.
I also think when you compare the price of an OS X version and what it comes with and then the price of Windows Vista... you kinda start to wonder if you really are getting the best value for your money.
Vista Ultimate is a great example - aside from the few bitlocker and encryption features enabled, what was really 'ultimate' about it? Those language packs?!
Windows 7 has done a great job at optimising Vista under the hood and strides in a intuitive Windows UI, however at some point they really should think about offering a suite of apps for free or at the least for a very low price. They're sort of already exploring this with their enhanced Live! Suite offerings.
People say that Mac's work out more expensive despite getting all the great software for free but i disagree - by the time you've bought Windows, a decent office suite, decent movie and photo editing apps with comparable UI-friendly-ness and power as the iLife offerings then you're already spent several hundred pounds on top.