I've been waiting for this for a while. I was an early Dropbox adopter, then I moved over to SugarSync about six months ago because the pricing is better. Now that SkyDrive is out and more or less replicates the functions of these services at a fraction of the price, I have no reason not to switch. Now it's between Google Drive and SkyDrive- I'm going with SkyDrive (I'm grandfathered into the 25GB free, which is very nice). SkyDrive is substantially cheaper, edits my Office docs natively at SkyDrive.com (whereas you have to first convert the doc to a Google Doc to do the same with Google Drive), and for some reason, I trust MS more with my data from a privacy perspective. MS's business strategy is to sell software, and free applications like this (which integrate deeply into Window 8 and Windows Phone 7) spur sales of enterprise software, whereas Google makes it money from advertising. Simply put, Google has an incentive to mine my data to sell me ads, and that makes me a little uncomfortable (just look to the tailored ads in GMail).
But yeah, with the latest update, SkyDrive is pretty sweet.