I mark mine up with an ol and bracketed counts – it was the best way I could think of to get all the information in one place. I did try ‘a’, ‘a em’, ‘a strong’ and ‘a strong em’ but I figure that the spoken-out-loud distinction is just too subtle and obtuse to be useful. I’m open to persuasion on that one though.

Incidentally, it’s worth remembering that a ‘tag cloud’ is actually a weighted list of tags. Weighted lists are a great example of information design: managing to convey lots of information in a very compact way. They are useful in contexts outside of tags too…