I got a beta account about a week ago using the link they posted on digg, and all of this new "Windows Live", "Messenger Beta", and the new Hotmail are all nonsense. Yeah, it's a nice spirit to see Microsoft having, but in the big picture, I don't think it's going to be as popular as some of the other well-known start web apps, like Google Personalized or Protopage. Even worse, they're using ASP as the backend! (Expected, but still agonizing). I think that only die-hard Windows users will be using this mainly.
The only nice thing it seems about it is that you can create "widgets" and put them onto the page. Not widgets that they've provided, but you can write your own code and stick it up on the page. Now, some other start pages let you make custom RSS feeds and such, but how many let you write your own code to make the widget do its thing (other than Google Personalized, of course)?
On Google Earth:
Well, it's been around for about a year and a half now and I must say that it is one spectacular piece of software. Even if there's still some bugs and kinks to work out in the official Mac version, the Windows version is kick-ass in the live panning, zooming, etc. and the entire globe. I can just imagine someone taking a video of the earth zooming into a house, and partway down fading gently into a filmed shot above the house, making a seamless transition all the way from space down to a very high zoom resolution (like, 1 meter or less). It would be a great opener for any speech, event, movie, etc. (and those of you who visited CES '06 may know what I'm talking about...).