Good article directories takes time to approve the articles. articlesbase, ezinearticles, buzzle all takes time to approve. but they are much more useful than our blog because they have more trustworthy domains and more trust factor than our blog. They update and index more frequently in a day than our blog and moreover they promote our blog itself if your account have some good authority in that article directory.
I am not against of blog submission it is also a very good method for site to gain backlinks and traffic.
Both are useful for site but it is totally depends on the self interest what he/she wanna to do more. I do both the activities for my site because Google gives preference to both ....