Users beware: just ignore startups altogether. A hot startup is a vehicle for converting user growth into money for the founders and investors. It does not exist to create and maintain a good product. It's fine to tag along for a ride; it's not good to make yourself dependent on its continued existence.

I think you can almost stop that at the word acquired. I loved pre-acquisition FolderShare. After Microsoft bought them, FolderShare was mashed into a bunch of aborted projects that sucked.