Note: I found this topic a good one to respond to because I just reformatted from Vista back to XP last night -- if you are bored and at work, this might be a funny read! This is MY VISTA experience.
Why I hate Vista:
When I first built this PC, I had XP on it. But my uni gave me an Ultimate copy free of charge, so I figured I'd reformat and try Vista. I knew everyone hated Vista, even people that never saw it, or used it. So I thought I'd give it a fair shot. My computer components at the time (and have since been upgraded, slightly) were fine for it. 4gb of ram (which of course only 3 were recognized, but still plenty) and a C2D overclocked to about 2.8Ghz, and an Nvidia 8800 gt. A good hard drive, good motherboard, good xfi sound card, and so on.
For the most part... it was okay. The aesthetic upgrades were nice, and while the administrator options were ludicrous, which I eventually turned off, it was all tolerable.
Over the last 5 months or so, I kept running into a lot of cockblocking on Vista's behalf. Since upgrading to that OS, it automatically (at least I'm blaming Vista for this since it was never the case until having it) disabled my keyboard and mouse from loading at boot-up. Making it almost impossible to get into my BIOS, boot menu, and so on. Unless I wanted to sit there for an hour restarting and smashing the keyboard hoping for that one time it'd work. Even that didn't bother me much, because I didn't need to get into the BIOS, and the keyboard was initialized upon desktop load, anyway.
Then we have the updates problem. Since Jan 26th, 2008, Vista just failed updating, every single time! I tried multiple things - going into cmd as admin and writing some asinine line of code out that supposedly set the updates back in place. Nope. Call me OCD, but even if most of those updates weren't critical, I don't like having an outdated system.
Lets not even bother with the USB hardware compatibility issue... one day my externals and camera work, the next day, nothing. Sometimes unplugging it thousands of times would work, but mostly I don't have time to pamper a system like that.
My favorite was when I was so frantic to leave for work that I accidentally clicked "hibernate" instead of "shut down". I'd never used hibernate, didn't need to, so I just left for work anyway. I came back home, and there was no way to turn the computer on. I tried hitting the keyboard, clicking the mouse (which was on), manual restarting. It was on, just not... usable. I finally gave up after 30 minutes and popped out the little cell battery. Then it was fine. At that time it was a "known" glitch, but really.. lets think of the average user. They would have just paid someone ~$70 to diagnose that, nevermind fixing it.
SO.. as of yesterday I was compelled to find a way to remove Vista from my life. Putting an XP cd in the drive did nothing, it would just float past it and boot my computer. Why? BECAUSE VISTA WON'T RECOGNIZE MY KEYBOARD SO I CAN'T SET BOOT PREFERENCES TO CDROM! That and Vista loves to ruin my life so much that it tried all it could to keep me away from XP. So I just start hitting the restart button and mashing F-12, hoping that just once out of hundreds of attempts I'd get into the boot menu.
YES! I'm in! Wait a minute... my arrow keys don't work. Awesome! Restart again. Maybe I can just get into BIOS and fix this keyboard issue. Another forty minutes of me hitting restart and mashing DEL. I get into BIOS but the only part of it I can get into is my 1st-2nd-3rd boot devices. I was furious, so I set them all to CDROM determined to get XP recognized at start. Still, I couldn't change the preference in the Boot Menu, so I didn't know what was coming. Restart. No XP install prompt. Seriously, Vista? SERIOUSLY?!?
While restarting endlessly, I'm searching around my house for an external enclosure, thinking to myself: I'll yoink out this hard drive and just format it from my laptop. But the only one I could find was strictly IDE and that didn't help me at all.
More hoping that my keyboard will be initialized at boot. I really wish I knew how, but I finally managed to get into the USB/peripherals section WITH working arrow keys! WTF!? I set the keyboard and mouse to work, restart, fix the boot menu.... and I saw the most beautiful screen I've ever seen in my life, albeit blue - my friends, this was not one of death. But one of purity, sanity and beauty. "Windows XP is initializing setup. . . " GLORY!
So why don't I like Vista? Because I don't like feeling stupid. And aside from being a little prettier, that's all Vista did for me.