Fastidious candyman What is Textile's advantage over Markdown or kramdown?
I use Textpattern and I'd like to keep blog and forum with the same markup. Simply that. I don't say it's better even if it has some advantages (acronyms, abbreviations and you have to type less brackets) but personally I would choose it.
Maybe textile is more a pseudo-markup language and Markdown concerns itself with writing content, maybe textile text is more readable...
p.s.: Markdown (and its dialects) is more popular but Textile isn't so unsucessfull (GoogleChat, for example, uses a Textile dialect).