I am sure there are a lot of differing opinions on this issue. As far as I am concerned, linux has been ready for the desktop for a long time :) I have been using it without any problems. Let me list the things I do:
1) Surf the net
3) Post to my blogs (Am at this time using a Linux distro, PCLinuxOS to post this running on a Pentium III 800Mhz laptop on which winxp would crawl and make me cry)
4) Listen to music cds
5) Watch movies sometimes
6) Rip cds
7) Take backups on cds
8) Take prints on my Laser printer, Samsung ML-1610
I am able to do all this on various Linux distros for a long time.
For me Linux always has worked on the desktop.