In the case of Dropbox, they need to go head-to-head with the Drive/Docs/Apps provision coming from Google. They're not as well-positioned to do that as they could be, and I'm not sure hackpad will be close to sufficient to get them there. But it's certainly a step in the right direction; documents are moving off the hard drive entirely, and there's no reason Dropbox can't help with the move to the cloud by expanding their offerings with moves exactly like this one.