Depends on the project - so many factors Desktop or Web? Data, Graphics, Game or something else? Who is the audience? Need to be expendable? Platform specific

Depends on the project - so many factors Desktop or Web? Data, Graphics, Game or something else? Who is the audience? Need to be expendable? Platform specific or agnostic? Input/output considerations? Single user, centralized or distributed data? If Internet/network what sort of connections will you need to support AS A MINIMUM? If planning to use commercial tools, can the audience handle the distribution/licensing requirements, costs? Update considerations - if a closed source single user, consider how updates will deploy in the platform you choose. Any special hardware you plan to use (i.e. pinpad, signature digitizer, fingerprint scanner) these will be a BIG factor on what you choose, sometimes such devices will narrowly define what is usable. Many of these are not much a problem by using more tried and true languages/platforms than something new as many of those issues have solutions you can just Google an answer. Going toward the newer/shinier platforms might get you an edge in some feature but may completely ignore other factors.