Always been happy with it.
I've got vista running on and HP dv9500 and an ASUS Eee 1000 and under both cases I've been really happy with it.
I know what a lot of people complain about, but really, I find most of them to be fools. Yes it takes a lot of the system, but I've got the RAM and if I want more its dirt cheap. Even with XP I wouldn't have used only 512mb or even a 1gb of ram. I would have stuck 2-4gb in there right off the bat anyways, its cheap, and more never hurt.
I've read many things about people complaining of instablities and annoyances. My experiences with such things? Well, I can't really think of any... oh, one comes to mind, the bloody system tray has the button on it to expand it to see everything on it, it wouldn't always work when pressed. Oh and when you turn UAC off that little red sheild is always in the system tray with its annoying red sheild-ness. And the last thing I can really think of is that connecting and managing net connections took some getting used to. While those things were minor bugs I can;t think of anything that really was huge, or even big enough for me to give it a second thought. I'm realitivly knowledgeable about computers and I tweak things to my liking, it doesn't take much, a few settings to change here, a application to add there. I really do have trouble understanding why some people have so many problems, am I just lucky?
Things I like, I love the start menu, the search is so useful, its basically an aplication launcher (something I had to add to XP). Its shiny and I'll admit I like that, gives me more to play with when changing themes and all. I appreciate the different default file arrangments, which make more sense then the XP ones (damn Documents and Settings folder), and I like that more programs seem to recognize and take advantage of this in order to make thing easier for people. I could go on with suddle things across the baord like that change in the file path bar which while making it bt harder to just type and exact location in it, does make it easier to see exactly where you are and let you easily go where you want by just clicking (besides if you're typing in exact locations idk why you'd be using the explorer and not just good old CMD).
I've got my Vista comps right next to my XP comp and its sort of a pain to switch back, maybe if you don't ever have the chance to try the two right next to eachother you'll never notice all the subttle differences, but I have and so have others around me. This is turning into a novel so I'll end it with this last thing.
I have a Eee 1000 with an 8gb SSD as the C drive, it runs vista, quite well I might add. I did it as a proof of concept to show people here at school who would throw empty arguments about how bad vista was at me that they could drop it, and they were general fools jumping on the vista hate bandwagon. The computer runs well, it boots quick (prolly mostly the SSD showing off there), the computer is suprisingly snappy, it happily runs firefox with multiple tabs with MS word in the background typing some notes (took a little bit to get used to the ribbon interface in the new word but I've come to appreciate it, especially how much easier equations and symbol insertion is, which is kinda huge for an aerospace major). I plays video fine, though HD is obviously out of the question, but thats a hardware limitation not a software one. I must note though that I have done a lot of work to the vista install I used. I cut out things I found unessesary, like UAC, the games it comes packed with, windows media player, and other such things I never use. Then once it was installed on the Eee, I found some nifty ideas to move all the windows dll files to the D drive in order to free up a lot of space, basically it just involved tricking vista into thinking the files were there on the C drive but actually directing it to the D rive. With that done and office installed on the C drive I'm left with 1.5gb of free space on the C drive, plenty of room for the usual fluctuating windows size.
So there, I'm happy, I'll be upgrading to 7 when it comes out, not looking at it as if its saving me from vista but instead as just another operating system to learn the tricks for (though I'll prolly keep the HP running vista, because I like to have multiple OSs around, and I just really like the changes I've made).