well sort of … lets look at this clearly…
Am i likely to be burning things to optical disc as a form of personal backup ever again ? …
the answer … NO.

Why ? well …
a basic internal blu-ray burner Price £160.00 pounds
amount one BD disc can store ? 25gb
cost of single sided 25gb disc ? £8.00 or more.
time to burn the disk … roughly 45 minutes to burn a 25GB BD ?(not a 4x drive to expensive)

At the moment you can buy 750gb external drives for a slittle as £85.00

So for the price of a burner and a disc or two, you can get 1.5 terabytes of permanently online storage ? the equivalent of having burn’t 60 blu-ray discs ? and having them hooked upto your computer in 60 blu-ray drives ? and you would have spent more than 45 hours of your time burning those discs.

so as a usable online storage medium its not worth considering, now if your desperate for small numbers of high capacity off site backups and money is no object then blu-ray might be worth considering, but to be honest a stored offsite hard drive not in general use would be almost as good a measure, and you could even afford to mirror it at this price with a second drive and you would still have an easier solution than a blu-ray one.

So in my opinion maybe blu-ray drives only real use are for sending large media files in the post, but only just, but usb storage keys will soon be equally effective at this when 16gb sticks come below £8.00 which i doubt is that far away.