QUOTE(Integration @ Jul 17 2012, 07:05 PM)

And now imagine a small, but steady Tetris community being confronted with a new game made by a big company, which is more advertised, which has higher search engine rankings, and so on. Some people will switch over for sure.
What does this have to do with copyright though? Say Blockbox or Cultris or Nullpomino had nothing to fear with regards of copyright - would Tetris Friends still not be made by a bigger company, more advertised, higher search engine rankings, etc?
Games like Tetris Friends have more pulling power because they have the Tetris trademark, and they'd have that regardless of whatever input devs had. And really, if they didn't and it was fine for various companies to put games out and call it Tetris, there's no guarantee at all that it'd really help matters, because you'd get tons of "Tetris" games of varying quality, and it's unlikely that the general populace would filter out the best one as their game of choice to have the highest search rank and such (just look at Neave Tetris aka N-Blox).
QUOTE(Integration @ Jul 17 2012, 07:05 PM)

Tetris Friends gave many games the last punch.
It quite possibly did, but I think that's largely irrelevant to copyright law and more down to the fact that most fan-made games were completely dead in terms of development. When was the last time TNET got improved? The gap between Cultris and Cultris II was absolutely huge too. Most of the fan-games that are now dead haven't seen any real development work in ages. When there are so many games to choose from then people are always going to be inclined to switch to the next big thing, and that's never going to be the game that hasn't seen any development progress in over five years. TF might have killed some games off, but if it didn't then TOP or Cultris II or whatever probably would have done anyway.
I think your point on copyright stopping teams of people coming in to try and make good, monetised Tetris games is half-valid, but I think that in practice it hasn't actually stopped it from happening. We don't have Blockles any more (though really, no great loss IMO), and Blockbox got hit with C&D notification that potentially resulted in the development work stopping (though I'm not sure - it was a while ago so I've forgotten the time scale, Deniax never said anything to that effect [and actually seemed quite amused by it at the time], and I don't know why they wouldn't also take the game down if they were genuinely concerned), but other than the recent Mino ruling there's not been a court precedent against fan-games and the general attitude has been "you'll be fine so long as you don't have -tris as a name".
Copyright is the reason we don't have TGM4, it's the reason that maybe we don't have (m)any professionally-made Tetris clones, but as far as the fan-game scene goes I don't think it's had much of an impact, because the mentality amongst the scene has been one of largely not giving a sh** about lawsuits because people mostly didn't believe they'd happen so long as they avoided the name. Sure it makes monetising games difficult, but a key aspect for most games that would be considered fan-games is that they're given away for free anyway and they're labours of love rather than investments of time and money expecting to see a financial return.
If by "fan-game" you actually meant "all unofficial Tetris clones" then sure, copyright hurts that middle ground between free fan-games and TTC products, but if you were actually referring to fan-games then I think you're wide of the mark. People who have wanted to make fan-games have mostly just gone and done it (even if they're not available beyond a closed group of people) with very little concern for gameplay copyright because until a month ago nobody thought there was any reason to worry (and based off the Mino case, if you're genuinely being innovative and creative, and increasing the "variety" in games out there, I don't think you have reason to worry).