i agree. tumblr is more of an aggregation of other blog topics + scraps as opposed to a real blog platform of sorts (basically a tumblelog). ive never been too impressed + probably wouldnt suggest it for any demographic outside of hobbyists at this point in time.
as far as blogging platforms, i have found wordpress (hosted or self-installed) to be the best out there thus far + have both utilized it myself as well as deployed for various clients with varying amounts of traffic + publication habits. moreover, WP has a steadfast following of opensource developers who are constantly improving + creating widgets + plug-ins for the latest technologies be it media, social networking, admin tools + so forth. that on top of the wordpress core itself being constantly updated + improved is a big win in my book.