Originally posted by RPS
They are official beta testers.
macosXrumors for one is certainly not a beta tester. They obviously have obtained "Jaguar" illegally to be able to post information and screenshots.
Beta testers have to sign a non-disclosure agreement in ink. If you leak information about the product you're testing, like macosXrumors does, Apple would be on their ass like white on rice. Since they are doing it illegally and anonymous ly, Apple doesn't bother. For some reason, they seem to like all the "Jaguar" hype they can get.
The truth is a majority of the users that run "Jaguar" on this website have obtained it illegally. It's quite simple to obtain.
When Microsoft beta tests software, you can actually just purchase the OS beta for around $20 and they will send you it on CD and any updates up until the gold master.
Microsoft makes their betas so after they expire, you can't install Microsoft updates making the OS pretty useless. Also, in time, new 3rd party software released wont even work with it.
As cool as the betas look, they are buggy and an overall headache to run. Speaking from experience, it's hardly worth it unless you have extra hardware you don't mind trashing.