The developers just told us that implementing the official level editor lead into some technical issues. We shouldn't hope to get the editor this week already. But the good news: A release next week seems to be pretty safe!
We can hope for a quite polished version as an alpha build and the Beat Saber Team really seems to put a lot of work into it.

The official information can be found here: https://steamcommunity.com/games/620980/announcements/detail/3199123443066805793

I wish everyone a great weekend and patience should pay out. :)