Recently I replaced my ubuntu 9.04 with LinuxMint 8 which uses Grub2 as the boot loader and I found it quite annoying for the following reasons:
1) There is no more /boot/grub/menu.lst to edit, instead, any new boot entries should be inserted into /etc/grub.d/40_custom
2) Adding a new boot entry or modifying boot settings (such as default timeout value) requires an additional command in order for the new settings to become effective:
[ update-grub also works ]
3) Because of the above reasons, if the LinuxMint can’t boot due to some misconfiguration in the grub setting, it becomes harder to get it repaired since you run into the egg-and-chicken dilemma: you have to boot into LinuxMint in order to get grub2 repaired and updated [ which is exactly the reason I don't like using boot loader lilo ]
4) The syntax has changed in grub2 for boot entries: among other changes, kernel is now replaced with linux, initrd is replaced with module (and module supports loading other things, this seems to be the only + point for grub 2)
All in all I was not impressed with the new “features” introduced by grub2 and as a result I downgraded it to grub using the other OS (Centos 5.4) on the same hard drive.