When I'm bookmarking a post on any given blog, I don't care whether it's in your "blog archive." What difference does that make? The point of the Title is to show the name of the page that you're on, not to help categorize the page. Use categories for this purpose, not titles. "Archive" is implied, and completely superfluous. (Consider: who needs to know that this is your blog archive? What is a "blog archive," considering that everything posted is in the archive? Doesn't that make the blog itself an archive?)

Second, when posting to Tumblr, the bookmarklet grabs the title tag to use for the link. To make my tumblog look uniform, I almost ALWAYS have to change the title around to this format: "Post Title – Site". The only sites that seem to do this properly are CNN and Yahoo!. If they do it in this format, why shouldn't you?

Why this is important: all blog writers are looking to increase their readership. Having people post your link on Tumblr helps increase your search engine rankings and your visibility. But anything that makes it more difficult for me to add your post is a general pain in my rear and makes me want to post your link less. Remove the barrier and stop with this completely useless "Blog Archive" tag. It doesn't benefit you, or the reader.

Good post, Sarah!