These forums cover sooooooooo much already, from application programming to web programming to web development to website promotion and SEO to tech support in windows, mac, and linux, to networking. It's nearly, absolutely impossible for us to cover absolutely everything computer related and every computer programming language available. (And there are lots of them!)
As far as application programming goes, we cover the big ones - C, C++, Java, Basic, and VB. We also have a Computer Science forum where you can discuss algorithms that are generic to all languages. Plus there is an "Other Languages" forum available for any less-popular languages.
Take a look at our ColdFusion forum, for example. Not very many posts, eh? That's because CF is not nearly as popular as a language such as PHP, for example. New forums are created as they are needed. If I start to see lots and lots of new threads and posts related to Delphi in the Other Languages forum, then a Delphi forum will be created out of demand.