It's interesting that workfront's helpdesk system is ZenDesk and not workfront. One of the things we were sold on for workfront was running our external facing helpdesk through workfront. This can be done, and we are doing it, but there are some annoyances with how workfront deals with certain things (Ideas for each are incoming) and I think all of our annoyances are the reason why Workfront chose to use ZenDesk. Instead couldn't' workfront just improve their product to help in the helpdesk area?
The idea exchange is great compared to the old idea location, but why can't this be inside of workfront? There's a list of ideas (Tasks/Issues) and then you could write your own front end that uses the api to use workfront in a new powerful way.
Dogfooding makes selling to customers much easier and would give everyone much more faith in the workfront product.