It isn't beta... it is DP (Developer Preview) and the 'Metro" interface (like anything 'metro') SUCKS.
It does suck. I loaded a laptop with it to check it out and I couldn't get the BIOS screen on boot-up anymore. So I wiped it.
I disagree completely. My Windows Phone 7 interface is fast, uncluttered, and intuitive. I (and my son) prefer the UI to on my WP7 phone over his iPhone's IOS interface. My wife is looking forward to upgrading from her Blackberry to a WP7 phone next year. My son is stuck with his iPhone a bit longer.
More Metro goodness on the way: WP7.5 "Mango" revision is due out in 2 weeks.
Also, if you really don't like the Metro UI, you'll need to scrap your Xbox360 and Live as that is moving to a Metro-like UI this Fall.
However, on a laptop running Win8, you don't actually have to use the Metro UI. You have the option of switching to the more traditional "Win7-looking" (explorer) interface.