I grabbed a LG GGW-H20L (BluRay burner) for my HTPC. It's mainly used ripping and occasional Blu-ray burning as I edit HDV&AVCHD footage frequently and wanted to have to have the ability to distribute it in HD.
Other than that a BluRay burner just isn't worth the cost atm, much like when DVD burner was first introduced.
If all you want is play/rip BluRay then obviously a BluRay combo drive is a better buy, until BD burner (and BD-R disks) becomes cheap enough which is still a few years away.
I had to buy a new DVD burner recently for one of my new rigs as its mobo didn't support IDE which meant I couldn't use my trustworthy BenQ DW1640.
In the end I settled for Sony AD7200S0 which is a NEC Optiarc 7200 clone. Customizable with Liggy&Dee firmware here.