But my Mini didn't have one, so I built an external one. I got an external enclosure, and a Plextor DVDRW drive. The Mini sees it when a disk is put in and lets me add/erase DVD+RW disks.
So, if you don't need one with you all the time, this might be a cheaper method for getting that functionality. I like this method since it lets me move the writer between my PC notebook and my Mac as needed.
I have removed the CD Burner from my MacBook about 3 times now, basically anytime my friend needs to do something drastic on his MacBook Pro since his DVD Burner is completely shot (will read 1 disk in 20). And it really is not that hard. Tedious, yes, but hard? No