Anyway, some stuff are still difficult to use it, for example, you have to click a lot to change a simple setting such as "Hibernate after x hours".
Managing file association is the biggest mess. My (advanced) file manager has a nice and handy tool that lets you to change file type associations in just 3 seconds. However, Windows 7 does not like you to do this from any other point expect its own bulky and difficult to use interface.
Under Windows XP, while performing regular tasks (programming, music, browsing), the CPU utilization was 0%. In Win 7 the CPU is usually at 30% even more. So, 30% of your CPU will be wasted for doing nothing (well, not quite nothing, probably for displaying the eye-candy Windows interface). If you look in Task Manager, non application is taking CPU, so probably those 30% of CPU utilization goes to the kernel/GUI.
Under XP I used to defrag my disk while I was working. Under Windows 7, the computer cannot be used when you defrag your disk. Even if my disk has a nice Experience Rating of 7, while defragging, the whole computer runs like a slug.
When speaking about reliability and stability, it seems Windows 7 needs several SP releases until it gets to the point where Windows XP is. Installed from the CD, it seems to be unstable. However, I let Windows 7 to upgrade itself and I got no additional blue screens until now. Let's hope it will stay this way.
Switching to a new OS without waiting for the service packs to be released may a hasty act. But it is also nice the breath of fresh air that Win 7 offers. Think only to those poor guys that upgrade to Vista in its early days. They were used a Guinea pigs.
I will recommend you NOT to switch YET to Windows 7 definitively, but to install it as secondary OS, especially if your hardware is more than 9 months old! Then migrate slowly your non-critical software (multimedia players and so) and leave the productivity tool on the XP machine. When you think Windows 7 is stable and fast enough (after you have upgraded your hardware) you can move to Win 7 definitively.
AMD 64 X2 Dual Core 4600+ (index: 5.4)
4GB RAM DDR2 (index: 7)
GForce 7600GS (experience rating: 4) :(
Seagate Barracuda (index: 5.9)