The phrase appearing most in my IMGDC notes, although no one actually said it, is “let a thousand flowers bloom.” Whatever fun or crazy idea you have, make that game. Independent studios have the freedom to try things that are too risky or quirky for big producers. Barriers to entry have never been lower, with improved middleware and distribution channels. Everyone on the forums who thinks he can do better has a chance to prove it.
Of course, Sturgeon’s law applies. Most of them are going to be crap. Have you been to a flash games portal? There are a dozen decent games of each type, followed by a couple hundred horrors. That is fine though, because players will tend towards the few quality games, followed by a long tail of niche games with implementations that appeal to a small number of people. Many attempts at low cost will produce a few gems, which can then receive greater attention.
By greater attention, I mean being bought by a larger company, unless your indie has the business framework to work with a million customers. That is a good problem to have, but it probably means you should cash out and use that money to fund your dream project. If you are not part of the crap 90%, you might have a sustainable niche game, and a select few will be bought out by EA, Sony, etc.
Or maybe they will just take your idea and run with it. I have not noticed Blizzard making payments to Games Workshop or the estates of Gary Gygax and JRR Tolkien, nor did Richard Bartle drive away in a gold-plated limousine.