Ummmm...Dropbox has had competition from the start. Skydrive, Box.net, Syncplicity and so on. So the article's premise really doesn't stand (though I don't disagree with him on the quality of Dropbox)
Dropbox has had competition from the start, but their specific focus was entirely different. Skydrive gave an enourmous amount of space for free. Dropbox made it easy to insure that your files are available anywhere. Even with Windows Live Mesh and 25gb of space, Dropbox is still far superior because of it's focus on "just works" file syncing and access.
This is so true. I have yet to find another competitor that even compares to dropbox. All the other competitors have their own client to move/view files (Receivd looks like it does too). dropbox works right away and the learning curve is nill. All you have to do is login and use your computer like normal.