I use Grub for historical (or is that hysterical....) reasons. When I first started using Linux, I had no problems getting it to dual (or triple) boot with OS/2 and Windows. The first time I tried to add a second Linux distribution to the boot, I ended up reading and re-reading the the Lilo man page. I know it can be done, but in the end, I installed Grub and found it much easier to set up a multiple Linux boot with it than I ever did with Lilo.
Its also useful that it can be quickly updated with no more than a text editor. My favorite trick with Lilo used to be making changes to /etc/lilo.conf and forgetting to run lilo. Which could have unfortunate effects. With Grub, I just edit /boot/grub/menu.lst and can then use it.
How much of this applies to the new all-singing, all-dancing Grub 2, I don't know - I've not looked at it yet.