We have a generic checklist to set client expectations and ensure that we do the major things in SaaS development like user management (registration, logging in, de-activations, password changes, etc), payment processing, etc. But as we work w/ clients new concerns come up like pre-demo testing on the staging server with the person who will be doing the demo. I'm just wondering if there is an established checklist out there. Otherwise we just keep adding to our internal checklist to cover new scenarios as they arise.
According to me, you should not go for a ready made checklist. More appropriate way is to develop your own checklist.
Understand you requirements, analyse them and then sort it in a form of a checklist. Then you can get feedback or opinions of others and see if it is adequate or if it need any improvement...
Hanu Kommalapati and William Zack layout a generic plan for the SaaS SDLC at http://www.infoq.com/articles/SaaS-Lifecycle.