I made some route changes to the Horde levels 43-44 sections. I have swapped 44 Dustwallow Marsh with 44 Desolace (the entire sections). This allowed me to do Deadmire (at lvl 43 instead of 38) and then go stop at TB to turn in Deadmire + The Black Shield at the same time, then fly quickly to do the Desolace stuff. Doing 44 Desolace is now mandatory because I think its faster with the new routes. This will also make the level 53 grind much shorter. I think these were great changes.
I consider myself a purist in that I would prefer classic to be released as close as possible to the original. Where that is on the spectrum of patch content will be up to blizz. I'm also not vane enough to believe that any single state of the game is the "Ideal" location we should be aiming for. There is common ground that we can agree on, and I would welcome more than a few changes as long as they are made in the spirit of keeping classic on the vanilla rails.
To actually get access to the beta, which has already started and continue to add more players, you need to sign up via your Blizzard account management page. Under Games & Subscriptions, scroll down to Beta Access and visit the Beta Profile Settings page. Once there, you’ll see a grid of available betas you can opt into. Once you’ve checked WoW Classic, hit Update Preferences and you’re set.