[mewzilla]

Oh, cheez whiz. I didn't even know there was such a thing as blu-ray. Is this like the whole cassette tape and 8-tracks, VHS and Beta thingie?

[Jedi Master Pikachu]

The Blu-Ray vs. HD-DVD is being compared to VHS vs. Betamax.

[Freeport]

Nope. Current CD / DVD systems use Red or Infra-red lasers to make / read tracks. Blue-ray makes use of a new (A few years old now) blue-purple laser and new media.

What's the big deal... It's the lasers operating frequency, laser dot size on the media, and storage media. But the bigger deal of the three is the frequency.

Since blue lights frequency is about 50% higher than red lights, the amount of data you can store in the same space is about double. Add that to the other two changes and where a DVD can store about 4.7 GB of information, the Blu-ray can store, for starters, about 25 GB (The technology can supposedly go up into the 40+ GB area).

Here's a reasonable explanation:
http://www.cd-writer.com/blu_ray_faq.html

[Vigilanteman]

If you haven't seen Sony's Blu-ray up close, you owe it to yourself to go to a Sony Store in your area (or even a Best Buy type outlet which stocks Blu-ray) and compare it to the HD format (which Sony also supports).

The detail and quality are a slam-dunk in favor of the Blu-ray format. Of course, if you are going to be watching talking heads like Helen Thomas, I'd stick with a 1958 9" black and white.