Post formats should be used as a way to signal the theme what part of the content should be emphasized, they got nothing to do with categorizing content. Problem is that right now no theme that I know of (haven't tried 2013 yet) does anything interesting with that information.

IMO this feature suffers from the "options instead of decisions" decease It only looks like the WP implementation is similar to what tumbler do, but in reality tumbler enforces many restrictions on what content can be associate with a format, something that WP doesn't do, and this restrictions pay off for both users and themers as they both know exactly what content to use and expect for each format.
The current implementation has too many options with no apperent distinction to the author. Maybe to make it more useful there should be a faster preview option when toggling between post formats.

The best approach IMO is to automatically apply formats based on the content as I suggested here http://core.trac.wordpress.org/ticket/23094.