Your friend is wrong. I'm sorry, but I've been using XP for almost 7 years now, and having 2 laptops that use Vista (neither belong to me, thankfully, but I still have to use them ocassionally) I can tell you 100% truthfully that Vista HOGS resources hardcore. My laptops both have 2 GB of RAM in them, and after logging in it takes a good 45 seconds before I can even do anything, and a full minute and a half before its finished booting. This PC, albeit using 4 GB of RAM, boots up in less than 30 seconds on XP, from cold-boot to desktop. My third laptop, in pieces now, booted XP in a minute (cold-boot to desktop) and it was using 2002 hardware, and had 1 gb of RAM.
Vista is basically unusable with less than 2 Gb of RAM, and even 2 only makes it just bearable. Vista can never run as fast as XP, even with 4 Gb of RAM running Vista only 3.25 can be picked up at the maximum (due to the 32 Bit Architecuter), so the only theoretical way of getting Vista to be blazing fast is having a rediculously expensive processor (Laptops are both running Centrino Duo at 2 GHZ) and using the 64-Bit architecture, which is even more buggy and incompatible than its 32 Bit counterpart.
And the reason everyone was chiefly throwing shit at Microsoft is because they promised a completely different operating system with Longhorn. Longhorn had people excited, and after the success of XP, people began to think that Microsoft finally had got its shit together.
Alas, Longhorn turned into Vista and the final version was basically XP with a new interface, a whole assload of bugs, and a bunch of bloatware included in the OS that both took up massive amounts of space (Vista takes up 15 GB to install) and slows the PC it runs on right down to a crawl.
And patching can't save Vista. Millenium Edition was the successor to Windows 98. Microsoft was fully expecting it to be the new industry standard, shipped in every PC on the planet, etc, etc. When it came out, the end of the world nearly came about. Microsoft was in hot water, so they completely abandoned ME and worked on developing two new OS's that would replace ME. They basically slid ME under the rug and poured 5 tons of concrete overtop, pretending that it didn't exist.
The same seems likely for Vista. They promised too much, and even if they do get some of the compatibility issues worked out, people will still be clamouring for a successor. Vista, with 100% compatibility is still on par or worse off than XP, which has better performance (in gaming and everyday tasks) and security that is about the same. Some revolution.
To put it simply, there is no reason to switch from XP to Vista. It has no selling point. Try and give me one reason why I should switch from XP to Vista, and i'll gladly take you up on it.
XP got its support life extended. I'm pretty sure MS would stop supporting XP this year, but it's been renewed into 2010, if I recall correctly. Either way, MS is responding to the outcry over Vista's suckiness, and they are well aware that they're in deep shit right now.
The final kicker is this: When one of these two things happens, you can rest easy knowing that Vista is completely dead.
1) Computer manufactures such as Dell, HP, Acer, Toshiba, etc, begin to offer either brand new PC's running solely XP, or the option to have Vista or XP preinstalled on the system.
2) Windows 9 comes out Holiday 2008.