Who do you mean when you write "they"?

The Flash plug-in Texas Instruments makes available to developers working on devices based on TI A8-based devices is ready. It is evaluation software, made for developers working on projects that utilize appropriate OMAP chips so those developers can test the performance of Flash on the systems they're building.

This does not imply TI has any intention of releasing the plug-in freely to the world at large. It seems likely that for such large scale distribution Adobe would demand different licensing, and a larger check, than for limited distribution, evaluation software.

The fact that Texas Instruments has a Linux-on-OMAP Flash 10.1 plug-in to distribute may not even mean that Adobe itself has that plug-in. There's been some indicators pointed out in this thread that Adobe (sometimes? always?) leaves Flash-on-ARM porting efforts to outside companies. It's possible that Texas Instruments paid licensing fees and developed the plug-in in-house or paid a third party to port the plug-in for them.

In any case, none of this implies Nokia has, and will be releasing, an updated Flash plug-in for Maemo 5 on the N900. It shows that Flash 10.1 on Maemo 5 is possible, but that was never in question.