That all having been said, hero points are a useful tool for changing the tone of a game. By providing a mechanism that allows PCs to usually succeed when they really want to succeed, you get a different adventure dynamic that works better when the group is aiming for a "pulp adventure" tone.
Hero points can also work as a feedback mechanism (where players earn them for taking cool, or otherwise genre appropriate actions) that encourages players to match the tone of the game. If players can earn a hero point for attempting a ridiculous stunt, players will attempt a lot more ridiculous stunts. That's a very efficient way to run a very different style game with the same core rules.
This is the way I like Hero/Action points. So I voted for in a module instead of core. I'm open to the idea of a really simply Hero/Action point mechanic that could be in the core, but I think they work best when they deliberately change the game in some way, which does point to module.
Perhaps a good compromise would be not in the core system, but a simple version in a module that was included in a sidebar in the same book with the core rules? I still maintain that the core rulebook(s) should have a few highly useful/popular options included, if for no other reason to encourage people to think about which options they want to use. Anyway, it's hard to say where such a rule should go until you see how the rule is done.
Also, as per above, I very much like the use of such points as an alternate "currency"--as they allow all kinds of nifty gamist and narrative play to revolve around them that doesn't work nearly so well with XP, treasure, etc. In particular, I've found that awarding bonus Action Points instead of XP for "good roleplaying", "clever ideas", etc, simplifies the game. For me, XP is a pacing mechanism for character advancement, and breaks down when it has anything else attached to it. I even used a modified version of the Arcana Evolved Hero Points for a replacement of the 3E XP cost in magic item construction.
Finally, I absolutely despise an Action Point mechanic that is based on getting a set amount per level, and when they are used they are gone. I dislike nearly as much such a mechanic based on the idea of very rarely getting them. It's not much of a currency if people can't spend them because they have to save them for an emergency.