For Ubuntu users, you can download the .deb file and do a sudo dpkg -i <deb file>.
The confusing part is that what you're downloading is a plugin for the Nautilus file manager, not the application itself. So when you're searching for 1.0.10 or whatever stable release, you get tripped up into trying to figure out why Dropbox is providing a 0.6.7 install link. The 0.6.7 is the version for the plugin, but application is something else.
What if you have an old version and want to upgrade? There is a selective sync feature recently released that makes it easier for you to manage which directories within folders actually get stored, which helps reduce your file space usage. It turns out the Nautilus plugin for Dropbox downloads the version and installs in your personal .dropbox-dist. You can check the version by doing a cat on the ~/.dropbox-dist/VERSION.
$ dropbox stop $ rm -r ~/.dropbox-dist/ $ dropbox start
You should notice that Dropbox will download the newest version. You can confirm again by looking at the ~/.dropbox-dist/VERSION file.