I have mixed feelings about the bug: I'm partly quite pleased that I seem to have found something that no-one else had come across yet, but also partly disappointed for the same reason. Although I don't suppose there are a lot of people desperate to have a managed class inherit from its own template template parameter, it's not quite as rare as all that since template metaprogramming in C++ has become more popular.
If I'm the first to come across it, after a long period in public beta, it does make me wonder slightly whether C++/CLI is being pushed in its capabilities by anyone, because I don't usually regard myself as a pioneer. I first came across it when exploring the possibility of porting some of Loki to C++/CLI (something I would have thought other people would already have tried, if only from curiosity), but only narrowed it down to the actual issue when I tried to use the same idiom in my own code.
I have worked around it in the situation where it arose, although it has resulted in less tidy code and some unnecessary duplication of template parameters, and I guess I know what to avoid in future.