I use and like Dropbox: it's robust and works well, but ...
When I share an individual file by publishing it's URL (copy link) to someone, when they open a file, like a video, on Mac, it plays the video. If they don't have QT Pro, they can't download it. I often want to share videos (my own, nothing copyrighted by others), and Dropbox makes that more difficult. I supposed I could just ZIP the video first, as iDisk does, but that's yet another step. They should deal with this issue.
Second, if I share a folder, there are two issues:
1. When someone else attached to it, we BOTH pay for the storage used - Dropbox counts the same bits twice. So, if I share a folder, then one of my sharees decides to move a bunch of c**p into into it because he's not a computer nerd like me, I go above my quota and have to tell him to get that stuff away. There's no way to restrict access (see #2)
Maybe that's OK if we both have read/write/delete access to the files ... but ...
2. Often files just disappear from my shared folders. Why? Because the most common use of these shared files if for people to drag them onto their hard drives for whatever reasons. And on Mac, that's a "move" not a "copy." So the file vanishes from Dropbox.
So I spend time warning my users not to do that, etc. What Dropbox needs is folder access types: full sharing for collaboration, partial sharing (read/write/delete, but not ADD files); and read only sharing (users can copy the files if they want, but can't make any changes)
iDisk was slower, but I could accomplish those goals easily enough.
