Mind your <b>‘s and <i>‘s. In a “semantic” frenzy, I once made the mistake of converting all my b and i tags to strong and em, even for non-emphasized words which should rather have been enclosed in dfn, cite, address, var, code, samp, kbd, or blockquote. That’s what the “semantic” is all about. Sure, it’s a few more tags to keep track of, but they’ll be directly related to the meaning of the tagged text, and can be styled accordingly.

blockquote is a bit confusing about that, as Andrei Herasimchuk rants. The blockquote tag is not a true block-level element on its own, but a container tag into which elements such as paragraphs (enclosed in p tags) should be inserted. MovableType (at least, the version that I’m using at this writing) is annoyingly quirky over that when in “Convert Line Breaks” mode, putting p tags around single-line blockquote tags. When incorporating blockquote into an entry, I need to turn off Text Formatting and do my paragraphs manually. I’m hoping the MT team can fix that in the upcoming 3.x version. (No, I’d rather not use a plugin.)