In the same way that using semantic tags when all you want is formatting is equally discouraged. Ideally (perhaps) there would be ways of indicating both semantics, and pure formatting.

You can still use <b>bold</b> and <i>italic</i> tags if that's all you mean, though I think that is rare.

If there isn't, then either solution is really equally bad.

True.

I would say that ''italics'' are very rarely used for emphasis in our articles, and much more commonly for simple formatting - names of albums, symphonies, quotations etc. I could be wrong there.

Ah. It seems to me that emphasis is used more often than simple formatting, and I was changing ''quote marks'' to <i>italic tags</i> in the few cases where it's appropriate, based on the way I learned when I first started editing. Then I was looking through the source code one day, and realized they were both being rendered as italics, so I was confused.

So, if I understand correctly, a bunch of people were misusing emphasis tags to mean italics, so someone changed the emphasis tags to mean italics, and now people are misusing italics tags to mean emphasis? :-)

: Are we going to change the dictionary definition colon markup to render as CSS indentation now, since many people use it for indentation?

What's the specific problem that <I> tags are causing?

None at all from a practical standpoint. Just curious.