Yes, but it's a terrible idea. I'm doing it because I don't use many critical apps at the moment, only calls, email, SMS, browser and music. Since these are fairly safe bets, I was willing to take the risk. However, "safe bets" still means "risky", and I can't assume that some foul-up in a future update won't brick the thing completely.
It is possible to roll back to 8.1 if you look for links explaining how to do it, but you could just wait a few months for the proper WP10 and let chumps like me risk our sanity for you in the meantime.