They are, but they still have a short shelf life and are locked down with copy-protection and not exactly portable once you have a large collection. I'd much rather have my HD content on external hard drive or on an SD card.
I have a couple of dozen Blu-ray movies, I have no intention of looking at them on a screen less than 32", there's no point. Why would anyone want Blu-Ray playback on a laptop computer, the iPad or any desktop with a screen of less than 24"?
As far as blu-ray storage/back-up is concerned, the average prices for recordable media (never mind RW) is £10 - £15 per disc in the UK. Why on earth would I do this, with 1 terabyte external hard drives available for £80 - £100. I've yet to do it, but I'm pretty sure it will take longer to burn a 5GB backup to a blu-ray disc than to drag 5GB of data over to an external HD.
It's amazing how people latch on to the few 'weaknesses' they can find (blu-ray, flash, front facing camera on a consumer media consumption device) and constantly repeat these complaints about 'omissions' and 'faults'. The majority of users don't need blu-ray on their home computers. For those that do, get an external drive and toast - no one is stopping you from having blu-ray, it's just not a standard feature because it's not what the majority (or even a significant minority) want. All it would do is push up prices at a time when people criticise apple's prices for being too high.
I can't wait for Apple to lead the way and remove optical drives from their line up, the uproar will be exactly as the loss of the floppy drive or the ADB/SCSI/Serial ports. Then in a few years, you won't even think about them. Fragile, limited useful life and bulky to store. An SD card will hold so much more data than a CD/DVD/Blu-Ray disc, with faster access times and less draw on battery, cost less to produce and be easy to carry around.
Bring on the future.