Youtube now plays?

I have off and on used the Tor Bundle. Now I am able to watch youtube videos? Confused by this, as doesn't this open me up to not being so anonymous?

I also notice ads now etc.

I downloaded the bundle and changed nothing on my end.

Thanks for any info!

Yes, in new versions of Tor Browser Bundle, javascript is enabled by default. Flash & Java - not. But youtube has also html5 player, so you can watch video even with no Flash installed.

Having JavaScript enabled DOES open you up to being "not so anonymous". The Tor Project admits this is a trade off in usability vs. security. They apparently think it's an acceptable risk, but personally I always turn it off.