I only change OS when I change to a new PC. Otherwise leave it as it is..

I am currently capable of keeping Vista skiny since two years so that it does not slow down the system..

Roger, many thanks for your 2 Cents comment.. sounds good. I would say it is worth 2 dollars.. ;-)

What did you use to move your application software when you upgraded to Win7.

My main concern is to reinstall all the software applications if I go to Win7 from Vista.

Sounds good.. Thanks..

I hope to meet you one day.. Are you coming to Munich office beginning of May?

I you are happy with Vista, don't change. You will change soon enough :)

If you need (one day) to re-install your Windows because of slowness, or because you have to many unwanted things, maybe you should go to seven. But now, why change something's working ?

To give my 2 cents, on every machine where I've switched from Vista to 7, (most were running from perfectly to reasonably well), I saw a notable improvement in the "user experience" as they say: more fluid, nicer looking, much better usability, and incredibly stable.

All in all, for me it was worth both the price and the hassle every time, even if your Vista is already running well, plus the upgrade process is pretty seamless. Where it gets a bit hairy and time consuming is if you are running XP and want to go to Seven...

@Ritchie: If you use the upgrade function to go from Vista to Seven, you don't have to migrate anything - it's a non-destructive process, that changes the OS without disturbing anything else, data or installed applications.

That's the reason why I said it that was more complicated when you had XP, because in this case the upgrade option is not available: you HAVE to do a clean install, and migrate your data and software.

With Vista, no problem: Just boot on the Windows seven DVD, and choose the upgrade option.

Absolutely - Change immediately. 7 is a HUGE jump from Vista - Way quicker, much nicer to use and the extra features are clever. 

As with all OS installs, I started from a clean HDD, rather than upgrading. This may take longer and require backing up any important files, but it means you start with a totally clean setup - HDD formatted and OS installed unfragmented.

One of my biggest concerns was something @Roger addressed, that I would have to reinstall things after the switch. The upgrade feature makes it nice, but you are still given a warning about reformatting and doing your own install for stability purposes.  I hopped on the Vista bandwagon pretty late, so I didn't have as many issues with compatibility and security.  For all intents and purposes, Vista had worked fine. 

What 7 does is create a smoother end user experience.  Again, much like @Roger stated, nicer looking, more fluid.  The Taskbar is a thing to behold, I just want to pin everything to it. =)

Some of my favorite features are auto full screening as you drag any window to the top of your screen, desktop slide shows and a sidebar that is actually worth using.  I would say this is the OS PC users have been waiting their whole lives for.