With owncloud if there's a fire in your house, or your cat knocks over a pitcher of water over your server, you lose your stuff. Plus it would be slow as dirt, since upload is limited by your ISP, and especially slow if you're traveling to some other continent. If you use a third party host you're basically as vulnerable as you would be on Dropbox, plus you have to maintain the thing and it's only a subset of the features. Again actual inconvenience for something (NSA snooping) you can't be sure affects you even in the least.
And beyond just being a subset of the features, it doesn't have Dropbox's ecosystem. Can you auto-sync your Oreilly Media books automatically with own cloud right from the Oreilly website? Does 1Password automatically sync with it? Is there a screen sharing app that automatically pushes to owncloud? Does it have a push API? IFTTT support? I, and others, use all these with Dropbox and it probably doesn't make sense to give them up because the NSA is the boogeyman FUD.
If you're specifically targeted by the state (especially extralegally), you're screwed. Personally, I just want to be in control of my data, and don't want others (government or otherwise) to be indexing or 2 clicks away from my data.
As you mention, hosting OwnCloud removes your cat/fire scenario. Even by hosting it at a US ISP, you are significantly reducing the likelihood that the government can index or be two clicks away from your data, and your host (unlike Google/Dropbox) isn't likely to be mining your data for future business models. Hosting it at an ISP in a country that respects individuals privacy (e.g. Iceland) means your data won't be in the government's hands unless you're directly targeted by a state actor.
A subset of the features is, for me, an advantage. Hosting my password database myself is a huge feature. My Mac's built in screen capture writes stuff to disk. I can set that to be the Owncloud folder. No third party app required! :)
Precisely my point. I don't / can't host in my house/office. And if i host on any remote servers, the servers themselves can be compromised or forced to. What guarantee they are not, if we look at the scale of revelations on NSA snooping so far.
And beyond just being a subset of the features, it doesn't have Dropbox's ecosystem. Can you auto-sync your Oreilly Media books automatically with own cloud right from the Oreilly website? Does 1Password automatically sync with it? Is there a screen sharing app that automatically pushes to owncloud? Does it have a push API? IFTTT support? I, and others, use all these with Dropbox and it probably doesn't make sense to give them up because the NSA is the boogeyman FUD.