Whenever I read something like this I can't help but think "Here's a potential customer to whomever can get this right and at the right price". It seems like there's still a huge opening in this market for someone to come in and take all of ZenDesk and eSupport's customers.
It always struck me that there was 1001 support desk providers out there... is there really that much space?
(cos if so it's going on my list of maybe projects :))
I do believe there is a gap in the market for a good but well priced product, but it wont be a simple little ticketing app, the creators would have to understand how support grows out of a one man job into a 50 man job.
eSupport offers a lot of tricks (well hidden in their horrific UI and UX) that save you time, you also have to handle that not just make a 'Oh a Customer has many Tickets!' ROR app with a nice logo.