This guy already said it best: http://www.quora.com/Dropbox/Why-is-Dropbox-more-popular-tha...
No, shut up. People don't use that crap. They just want a folder. A folder that syncs.
Apparently every time somebody at Dropbox suggested more features, he was simply told to "shut up." It sounds like the Dropbox guys got it right simply by being not retarded, like the commenter but unlike any of their competitors. Not really; according to the Syncplicity guy, Dropbox built multi-folding syncing and discarded it after they realized they couldn't make it simple enough for users. The lesson is not to "shut up" and listen to people who know what they're doing; the lesson is to design your UI carefully and pay close attention to how users actually use your product.
No, shut up. Most of the world doesn't sit in front of their browser all day. If they do, it is IE 6 at work that they are not allowed to upgrade.
As the Syncplicity founder pointed out, it was more important to get coverage from tech journalists using Macs. (After all, if folks are stuck with IE6 and aren't able to install Firefox, how are they going to install Dropbox?)
There's some real gems in here from the founder of Syncplicity.
For instance, not having a Mac client meant that the tech press wouldn't touch it. Then, they wouldn't write about it. That's pretty enlightening.
Apparently sometimes a small minority of customers still can make all the difference.
Adding Mac support didn't make DropBox any more complicated for the end user -- there were no new corner cases or potential conflict scenarios, no new steps in the setup, no additional configuration complexity, basically no cost at all in terms of end-user mental load in order to extend their product beyond the Windows platform and reach some important taste-makers.
This is distinct from the end user confusion created by adding, say, multiple folder support or any of the other complex features and configuration options that users will clamour for. When you don't carefully curate those kinds of features, you end up sticking your users in tyranny-of-choice territory in a way that simply broadening your platform support doesn't.
I suspect that's not strictly true. Mac OS X and Windows file systems are subtly different in features (hard/soft links, aliases, .lnk files; files with multiple streams; various Finder annotations to files), and I suspect that once you sync to both Windows and Mac you will run into weird issues. Of course, syncing to multiple platforms is probably only something "power users" would do, and they can tolerate some teething problems.
Leaving out Mac support in this case is like opening a coffee shop that sells $4 lattes, but can only be reached by people driving beat-up old Fords and Chevys.
I agree with your first paragraph but would note that I think you're shooting for "Leading edge" rather than "trailing edge."
Basically, active engagement with journalists is key to getting the right press, especially in a competitive market.
The designers found that nobody used word count - except for Journalists. Guess who write reviews of new word processors?