I'm personally stil sticking to Delphi. The main reason for this is the fact that not so long ago I invested in buying Delphi XE2 proffesional. So if I switch my development tools not it would seem that all that money was just thrown away.
Besides currently I'm only targeting Windows platforms since I know it prety well. But this doesn't mean that I'm not thinking about going to other platforms in the future. Thats why I'm already trying to use such components which already have support to other platforms (mostly being compatible with FPC) and I try avoiding ause of any Windows only specific code as much as I can.
Right now I'm decing wheter I should or shouldn't use OmniThread library. While OmniThread library alos you to easily make Multithreaded applications it currently only works on Windows based systems. Also based on Primož Gabrielčič's words there is no plan of porting OmniThread library to other plaftorms for now as it would require compleete rewrite of the whole library as it heavily relies on Windows functionality.