One would hope ...
... as it has been made (or is in the process of being made) into open source and all that, but then, ultimately, it is thoroughly screwed as a development platform, especially so with Nokia's deeply mystifying additions. Slim hope with Qt+Symbian, though, if they ever get it to work as to completely hide the underlying platform and/or modify it so that e.g. multithreading and normal use of standard C++ is not sabotaged by platform design. It will probably take too much time before this is 1) realized, and assuming that 1 eventually happens 2) implemented; meanwhile, the crucial independent developers have gone elsewhere.
It might make sense to simply discard the upper layers of Symbian as it is now (assuming that the lower levels are in fact decent or can be made so) and replace the upper ones with, say, Java (as, I seem to recall was done, with Android). Then again this is probably an IP (sw patent) minefield.