Status+of+Online+Support+for+Mathematics+Discussions

In one short paragraph, without too much detail, how would you summarise the support for mathematics, including algebra and calculus, on Web 2.0, social networking and other websites? Please add your reply as a comment under the topic [|Status of Online Support for...] under the Discussion tab of this page. You may cross-post your comment to the [|same topic on Mathematics24x7], if you wish. This discussion is based on recent questions by [|Maria Droujkova] in her weekly online mathematics meeting.

//Twitter hashtag: #mathmarkup, for LaTeX, MathML and related topics about mathematics markup.//