Since this thread is 95% speculative let's continue in that vein.

What if for whatever reasons the Flash 10.1 plugin that was demoed will work in Maemo but would require retooling for MeeGo? Depending on how it's coded I could see that being a possibility. So what if Adobe says "Time out Nokia-- you killed the natural upgrade path for what we were working on, we think your user base for Maemo will be too small now, and we see no reason to commit resources to it any more. So, plug pulled. We're moving the team 100% to MeeGo."

Now, someone can poke a hole in that by showing that there would be no such code migration issues.