If you want to see how Flash runs on the HTC Hero, feel free to head over to Adobe where they've got a video look at how it all works. Overall, everything about Flash and Android looks pretty darn good--you can double tap to full screen flash videos, play flash-based games, and even access web pages that utilize Flash. For the video they played the trailer for Transformers 2 and utilized Expedia's Map feature (which is flash based). It's pretty much everything you ever wanted to do on the web, on Android.
As an added bonus, you'll get to see multi-touch demonstrated in the video as well! (hint: it works well)