Syntax highlighting needs a shared XML spec. Every different editor has a different file format for specifying keywords, tags, etc. And this clever tool has, sigh, yet another one.

I find that among the various investments one makes in an editor/ide/tool for coding, anything involving language specific customizations becomes hard to leave behind.

In the words of rusty "XML is like violence: If it doesn't solve your problem, you aren't using enough of it." :)

I think that's partly to do with the number of languages "supported", it's basically chosen quantity over quality (for instance you can't even have different colors for "inline", "static" and "volatile"). For the main language I care about, C, I ended up writting my own highlighter for html. And possibly because it only supports C to HTML it produces a much better quality output (and it's not even a real project).

Highlight also suffers due to the copious amount of crap "themes" it comes with (and the default one isn't that great).