Aero & 3d windows - see everything you have open all at once
Windows Movie Maker, as a holdover from (XP MCE and XP Pro).
Windows DVD Maker
ability to handle large-sector hard disks. this capability is already in windows 2000 somewhat if your hardware can handle it.
[it is unknown yet if they fixed the 2.2TB volume-size limit in Vista. Real problem if they didn't... RAID boxes and NAS wouldn't be very useable, and the upcoming 2 and 4TB disk drives are going to make things really interesting.... I am still searching the Microsoft and the MSDN for articles to this effect]
can still run DOS (if you buy 32-bit Vista), win9x, XP apps... most of the time. If you are on 64-bit, get VM-Ware to run DOS apps.
parental controls on time usage for user accounts. monitoring too.
parents can monitor children's internet activity.
can search for documents and applications quickly using search bar (Instant Search). I hear this is also available for XP as Desktop Search.
smart-stitch photos together to make panoramics or tall portraits of buildings and things like the Washington Monument.
has all the stuff of XP Media Center Edition (record movies, TV Tuning), make slide shows of your media. with multiple tv tuners, you can record one show while watching another.
More secure than XP.
Why you should not buy vista (cons)
There is a lot of software that won't work with Vista. Companies are having to come out with Vista-compatible versions of their software.
Mac has better equivelant way of handling security
security keeps bugging you.
they took out Start|Run from the menu (however, you can still do a windows-key R. instead, you must search for the executable (which takes a long time) and then double-click on the correct one. Regardless, you should still be able to run items using [windows-logo-flag-key]-R. The Windows logo key looks like a little flag. Unless you are one of those who used it on a regular basis in XP, you would not know it was gone. you can get it back by right-clicking on the Start menu|Properties|Customize|Advanced. search for "Run command" and make sure it is checked.
high system requirements!
directx9 video card (make sure it's a newer video CARD made for Vista, not just built-in motherboard video) with 256MB video RAM
512MB System RAM (you really should get 2GB RAM minimum)
enough HD space to hold a DVD (10GB+). 80GB is a minimum hard disk with vista.
Dual-core, AMD X2, or Dual-procssor I think is a minimum. you can get by with 1 processor or core, but it's really going to be slow and hard to use! If you can do Quad-core (4-core), all the better.
There are several new heavy background processes in Vista, like the indexing service (not sure what it is called - Offline Files I think) which chugs the hard disk so you can do common application and desktop searches, a primary task in Vista, and the service that does Aero (called Desktop Window Manager Session Manager), the Themes
service, and especially the memory consumer Superfetch, which prevents apps like Photoshop from working and causes others to crash due to lack of memory.
This makes it a bad decision for laptops if you want to run on batteries - but we will see how things go: SP1 should bring a performance optimizing tool that lets you turn off Aero and the like, but it is only for Business, Ultimate, and Home Premium if I am correct.
2 (out of very many non) reports of "no memory for programs" due to SuperFetch and other memory management issues. Not sure how real this problem is yet though.
Vista runs down batteries on laptops - several services constantly run the hard drives. There are things you can do like turning off Superfetch and other tweaks to make it more like XP.
Superfetch service is giving problems by taking memory away from apps for use as disk cache. Sky is the limit on memory usage. apps are breaking, crashing, and not working.
downgrades quality of images if non-certified HW is used. (Output Protection Manager)
downgrades playback of audio if non-certified HW is used. (Output Protection Manager at it again)
SP/DIF audio interface will always be disabled by Vista because of Output Protection Manager.
non-Vista-certified audio cards will be disabled by vista according to article below. (Output Protection Manager)
Dangerous for medical imaging in life-threatening situations! (Output Protection Manager, not to be confused with VistA Imaging EMR). downgrades quality of images. a security "feature" of vista. see article and web page. what this comes down to I think is that you are not using all Vista-certified media hardware, the Output Protection Manager (a part of Vista DRM Protection I think) will ruin your multimedia experience (video, audio, images).