Runs great on my rig - Vista 64 bit ultimate
Runs good on my buddies as well - Vista 32 bit Ultimate

I would seriously suggest a fresh load for it, not just an upgrade.

Couple other things - how much RAM do you have, and how fast are your harddrives? Hard drive speed really has a dramatic effect on how well Vista runs. Just some things to keep in mind. RAM and Processor are important as well (that goes without saying), but the hard drive speed really does impact that OS dramatically due to all the writes/reads that go on as it loads and runs.

2GB Minimum as far as RAM goes.

Yeah unfortunately you will be dealing with the (at least) 10% drop in performance in vista over XP on the same hardware. So make sure you have a pretty fast rig if you want to play reasonably high settings at 1680x1050 or higher res. This game is a bit of a pig for what its doing visually, supreme commander runs almost as fast and it has a LOT more going on visually most of the time (and I still wouldnt consider SC to be an efficient game). The devs have promised improvements, but its probably always going to be a little sluggish.

Personally however, I've had graphical lock ups and worse frame rates in vista than XP. I know because I also just went through the XP to vista upgrade very recently (post 1.03). I did the full install, not upgrade from XP, so without any change in hardware, these have been my experiences. Honestly, vista isnt for games yet unless you have a top of the line rig.

Perhaps my problem is that I dont have a FULLY vista compatible vid card (7900 GTX - so no dx10). I couldnt say if my aging hardware (18 months old -oh noes!!) is the issue or not.

EDIT: looks like the guy above me answered some of the issues I have, 7x drivers are not so good.

Sins on my system (Core 2 Duo, 4GB RAM) runs awesome in Vista Home Premium 64 bit.

I highly recommend against Vista unless you have at least 2GB of RAM. Its a bit of a memory pig. But if you have a system that can handle it, Sins will play just fine.

(One thing: In Vista, Sins appears in the "Games Explorer", rather then in the "all programs" area of the Start Menu. I find its actually easier this way because all your games are together in there, but it can be confusing for a new user.)

Ok ok fanboy, hold your horses, yes my mistake, Ironclad, yes I have an older card. But Im sorry, poor performance for something that arguably looks no better than homeworld 1 should NOT be the case. The comparison to Crysis was a bad one, they have vastly different environments to deal with. However, I think the comparison to Supreme commander holds up, the first game runs very smoothly on my machine. Why does one game with a higher visual quality (yes IMO but what other guage is there for these things?) run smoother than another game that has to deal with comparable issues?

Anyway, I don't want to get into an argument over this, its just a little disappointing that pc games in general don't come with that locked down solid feel any more. Patches are the norm and bugs for 25% of the user base are acceptable upon release.

SO who's running Vista 64? Running any other games besides SINs?

COD works flawlessly, Hellgate London (when I had it installed) ran great. WoW, the rest of the guy that Tridus has...

I have only hit one game that it didn't like, Heroes of might and magic 5.

Other than that it seems good to go, though I have a dual boot with XP 64 just in case.

Setting up a dual boot is ez mode, just install XP first and Vista sets up the dual boot flawlessly.

Good luck, you will be pleased. Most haters talk trash about Vista, personally I have no problems with it and find it to be a great operating system overall that I use at home and at work with equally good results.

No Problem in my Windows Vista ultimate 32 Bit.  

Haha, yeah if you haven't figured it out already I'm given to exaggeration, but I have to say when I first saw screen shots of SINS I really thought, oh sweet its homeworld 3! But why are the graphics worse than 2? Then I read that it wasn't really a space rts and I forgave them. However, the fact remains that this game doesn't measure up to a game thats almost 5 years old visually. Sure, sins has anti aliasing and more glow effects (all of which produce horrible fps issues in larger battles) but those dont make a game look better in my opinion. Those are the glitter that is added afterwards. What makes a game like sins look and feel great is the ship design, the scale they adhere to (much more convincing in all aspects in homeworld - a large ship looks HUGE as it should) and the way the end result is presented (homeworld has far better lighting than sins, you can barely see ships in sins half the time, just try playing in cinematic mode for 2 minutes, you'll see what I mean). Also, random backgrounds and the way they make half your units and structures nearly invisible if you get the wrong icon color/background color combination is kinda awkward at best.

Anyway, sorry about the off topic rant, I just had to make my previous point a little clearer.