Let's look at the first one first. Windows 95 in many ways introduced "the" Windows user experience. It was a clean, reasonably logical user interface that was surprisingly good from a user interface perspective considering the limitations of the underlying platform, limitations which were necessitated by the limitations of the underlying hardware and the need for DOS compatibility until Windows-specific software arrived. It was Windows 95 that I evaluated, then went to my boss and said, "This is going to be big. We need to figure out some way to make money with it." That was a few months before a customer brought Linux to our attention (and my reaction to that later -- it was not favorable, initially), but certainly I wasn't wrong when I said that to my boss.
It's been all downhill since from a user interface standpoint, with each new release of Windows having yet more useless folderol to waste resources and confuse customers but no fundamental change in the UI. Windows 7 continues that tradition, adding lipstick to the pig that has become Microsoft's overly complex user interface by re-naming some things, changing text to icons on the menu bar, and somehow managing to make the Control Panel even more complex than it already was. People who claim Windows 7 could somehow be a "Mac Killer" are being ridiculous. Changing the text on the menu bar to icons does not make it a dock, and Windows 7 is even more confusing to set up and configure than its predecessors were if you're trying to integrate it into an already-existing network. I clicked away in the control panel for quite some time before finally typing "change workgroup" into the search bar. That took me to a place where I could change the workgroup (so it matched my home and office workgroup name so my systems would appear in the network browser), but where is that located in the morass that is the Windows 7 control panel? I have absolutely no idea, I clicked into the logical place and it changed my workgroup to "WORKGROUP", which isn't what I wanted at all.
Meantime, click on the open-apple icon and select 'System Preferences'. There's two possible places where you could set the workgroup -- 'Sharing', or 'Network'. I clicked on 'Sharing' and didn't find it, so I clicked on 'Network', there's a button 'Advanced', I clicked on 'Advanced', saw the word 'WINS', and yep, there's my NetBIOS name and workgroup name. Three clicks once I got the Mac "control panel" up - Network, Advanced, WINS -- to get me where I needed to be.
So from a user interface perspective, Windows 7 definitely is lipstick on a pig. It's just a bunch of lipstick on top of the original Windows 95 user interface, and like a toddler messing with mommy's lipsticks, the results are not all that great from a usability perspective. Frankly, I prefer the original, which was fast, clean, useful. However, that's not the important changes that have been made to Windows 7. The important changes are under the hood. Windows 7, in my test, used approximately 3GB more disk space than Windows XP -- i.e., around 8GB rather than 5GB. Its memory usage for snappy performance is approximately 256MB more than Windows XP (around 756M vs. 512M) if you disable Aero by switching to a 'Basic' theme, and since Aero is just lipstick, that's no big deal. In exchange you get a more secure operating system that has built-in functionality that Windows XP lacks, such as the ability to record a DVD. I have not tested Windows 7 on a netbook yet, but I'm not seeing any reason why it wouldn't work -- even with Microsoft Office installed and various third-party Internet software (Firefox, Safari, Flash, etc.) I'm using only 14GB of disk space for my Windows 7 system, and even low-end netbooks come with 32GB SSD drives and 1GB of memory today.
So from that perspective, Windows 7 accomplishes what Microsoft wanted it to do -- it allows them to discontinue support for Windows XP because it will run pretty much everywhere that XP is currently required due to the resource usage of Vista. It also accomplishes what most IT people want -- a more secure operating system that won't require them to spend half their time cleaning up after virus outbreaks, and which allows them to standardize on *one* operating system, rather than having a mismash of various versions of Windows. On the other hand, it's pretty clear that Microsoft needs more than lipstick on a pig to clean up their user interface. They need a few iFools to lead the charge against useless UI complexity, including at least one iFool who has the status in the corporation to push back against the marketing droids and geeks who always want one...more...feature... to never be used by actual customers, but look good on a marketing flyer or looks, like, really rad, dude. I wish them luck, because after fifteen years of putting lipstick on a pig, there's almost more lipstick than pig insofar as the Windows UI is concerned.