The idea is nice but yeah all the other distro's we would need to some how link with. Also @DarkTAO with those like me who have nearly 700 games. God I can see it now. ping ping ping 700 times. *hits turn of button* Does not work NO!!!
DarkTAO touched on something that I would like to see that wouldn't require account linking but simply having a public Steam profile.
I own over 5000 games on Steam and the ability to see which games I own have active trainers would be invaluable to me.
I would think it could also help on the business end for you. Potential customers could enter their Steam profile name and see a list of games that they own that currently have trainers. I did it the hard way before I became a life member by alternating between your alpha listings and the search feature on your site to see if your offerings were worth the cost. People with small libraries would probably find that you offer trainers for the vast majority of their games and what better reason to go lifetime.