Didn't you hear dejavu? Hylis said on the developers blog that new blocks for Canyon are coming. That wasn't a theoretical statement, that was a definite statement of news. Clearly they haven't "forgotten" about Canyon. I have to believe Canyon will benefit in some way to the bug fixes and updates that happen even in ShootMania since the systems are so connected. Plus ManiaPlanet 2.0 is coming, and Canyon will benefit from all the improvements that Valley will receive as its being beta tested, etc.
I think you'd be seriously in denial to say there's not problems with Canyon. The more we play it, the more things pop out at us. But you could be equally ignorant to think Nadeo doesn't care or that they won't do everything in their power to improve the game over the release of the next 8 titles/environments. They're only human though, and they've taken on a lot for a small team. I have no doubt they'll achieve their goals. Some people may get annoyed or even bored along the way, but those of us left will look back in 4 or 5 years and think of the amazing adventure we got to share with Nadeo, among one of the most community oriented developers on the planet.
Read through some of the posts Hylis has made on the forums and it becomes quite clear they're very interested and invested in the success of Canyon, but maybe more importantly... in the success of ManiaPlanet. Only when more environments get released will the game begin to be fleshed out and show some true diversity for a variety of players.
Just hang in there guys.