[jonathanmoore]

With most platforms that is a valid concern, but with Tumblr you can easily create a local backup your entire blog (http://staff.tumblr.com/post/286303145/tumblr-backup-mac-bet...) as basic HTML, images, assets, theme, etc.

With that said, Tumblr has a very bright future ahead of them.

[pavel_lishin]

Sure, but then you're stuck setting up again elsewhere - so why not do it from the start?

Answer to rhetorical question: because we can't be bothered, so we'd rather just pick a provider who is more likely to stick around than not.

[spinchange]

That's a totally reasonable consideration but the revenue model of the host platform isn't always the best indicator of its success or longevity.

LiveJournal & Six Apart have longstanding revenue models but aren't hosting users like the President of the United States or large corporate media entities.

[pavel_lishin]

Sure, but they're still around. Or are you implying that the President and Corporation, Inc. would bail Tumblr out to keep their blog up?

[wmf]

BTW, that backup app is even less reliable than the rest of Tumblr. I did manage to get a full backup... once.