Steven made the following blog post Saturday
It is a sad day when I have to wave goodbye to one of my favourite projects, but it's just becoming uneconomical to continue development on Stack for iPhone/iPod touch so I must let it go.
I have to work extra hard as it is on creating things for the App Store, but when people like paniK go ahead and make my software available to pirates and I watch sales vanish overnight, it means I have to spend much more time on marketing and development for my App Store apps to try and offset my losses, leaving no time for projects like Stack that earn me nothing.
There are several hundred thousand users of Stack at the current time; thanks a lot for your support! I'm sorry that I can't continue development - I've put too much effort into it so far at the expense of my other projects (and Real Life). The only way I can foresee a reversal of this is if either the pirates stop or sales of Lights Off increase; both are looking very unlikely.
Stack will be removed from Cydia soon, so please grab a copy for yourself quick if you wish to keep it. Existing copies should continue to work for any jailbroken 2.x version of iPhone OS.
I know this will upset a lot of people