Decaflon

You will gain absolutely nothing from running vista, and you have a list of potential problems, or at the least possible upgrades that are necessary.

Buy a Mac!
I was comtemplating the same thing when it came out but I bought an iMac instead. I'll never go back to Windows.

You won't have any issues with any of those applications (provided you get the Dreamweaver 8.02 patch). Oh I can't speak for Zend but that should be a google away.

As for benefits, as an aspnet dev, IIS 7 was probably my biggest bonus but there are quite a few things in Explorer that have been "upgraded" which makes wanking around with directories a lot faster and easier.

Other than that, it's just gloss.

One problem I've had is running old versions of IE for testing but I've countered that with a Win2k and WinXP installs in VMWare. You could easily do the same with VirtualPC for free... Just be aware it's an added hassle.

Yeah I would go the Mac route, then you can have both.

Buy a Mac used to be my option. However, in my country Mac is not supported well. It is difficult to find MAC software and hardware in my country. I have tried a G5 before, it is really great.

There's a Pre Upgrade Tool that will look at what you've got now and tell you of any potential problems. It's a good idea to turn on any devices that aren't on all of the time like printers and scanners and such like so that they're included in the testing.

I ran that, gave me the all clear - told me to get rid of my antivirus and update it to a newer version and get a new driver for my scanner.

Since upgrading I've had no problems and I think it's wonderful.

I downloaded every alpha/beta of vista, and even have a copy of the final release, and in all honesty, I'm sticking with XP for now. Vista has just jumped too far, without enough innovation. Apple was already doing a lot of this stuff a long time ago. The most major points are that Microsoft has completely re-engineerd a lot of the essential things, and companies are struggling to keep up. Nvidia and Creative are prime examples. Nvidia can't keep up with driver issues, and creative has to to put up with the fact the Microsoft totally re-created the audio stack, so that means developing completely new drivers. It also means that VERY few past and current games will work properly on vista because the games are incompatible with a lot of vistas new programming. It also requires a hugely powerful system to run very well. It runs on low spec machines, but watch it stutter. Most of the changes from XP are just cosmetic anyway, as much as it's nice, I couldnt justify the cost and performance hit right now.

In short, I'd wait at least another year untill the prices drop, there is proven hardware and drivers, and Micrsoft have patched it enough to make it more stable.