I thought it was obvious at first glance he'd be promoting his own site anyway; his username is 'sideproject'.

Personally I think it beats Show HN: Sideprojectors, which was his alternative. I saved the list in my notes. Thread was useful to me and good advertising for him. Win-Win.

Exactly. No need to complain about win-win scenarios that aren't coercive.

Agreed, I think it's a great way to market your service - with a list of alternatives included.