I'd phrase it slightly different: What you will be able to do in HTML5 everywhere tomorrow, you can do in Flash today on desktops (assuming your browser does not crash and you can live with the roaring sound of your cpu fan).
Or even better: What you might be able to do (pending royalties, patents) tomorrow with HTML5, you can do with Flash today without worry of being pursued by a consortium representing a specific codec you may or may not be allowed to use.
The "my fan turns on when I use Flash" is weak. I use a MBA and I can tell you just about anything involving video or any sort of high resolution graphics gets "the fan spinning".
I love the "you can't play Flash video for more than 6 hours on mobile devices!" argument, too. You know what else I can't play for 6 hours? Angry Birds, Netflix, Sonic All Stars Racing or even TuneWiki (audio) or any of the other semi-demanding apps I use. So Flash is supposed to be better than all that?
