Unfortunately the upgrade means that games that run on the 3GS may not be able to run on the regular 3G (3G games will work in the other direction though). This means developers have to decide whether to support the “new” platform, or simply continue to offer games that will be compatible for both.

IndustryGamers recently asked a few developers if the new plan was worth developing for.

According to EA Mobile, it absolutely is. For many games it sounds like EA will develop two versions, one to run on each of the phones. Other developers, though, don’t share EA’s enthusiasm. Sega, for instance, will only be developing multiple versions for select games, while the rest remain compatible with the 3G. Digital Chocolate is the downer of the group, saying the 3GS will improve existing products to the point that there is no need for a separate release.

Right now this might not mean much since we’ve not yet played a 3GS optimized game. The guys at Firemint, though, are eager to show off 3GS capabilities in their new racer. Check out the demo video on YouTube. It’s pretty damn impressive.

id co-founder John Carmack told Joystiq today that he is “passionate about the benefits of the iPhone,” and that his company has a lot of fun porting their titles. He also says it doesn’t require a lot of focus, at least for an established IP like Doom. But there is more to come from Carmack and company, who recently announced their buyout by ZeniMax, parent company to Bethesda.

“I’ve got a slate of iPhone titles, I expect to have an iPhone release every two or three months for the next year,” said Carmack. He made it clear that the benefit isn’t necessarily the money, but rather the level of commitment. When a game doesn’t cost millions of dollars to make and market, it’s a lot less pressure on the development team, which Carmack views as a good thing.

I’m glad to see a major developer taking the iPhone into serious consideration. Titles like Myst have recently been ported as well, but how about some new IP? Personally, I’d love some.