There is an abuse of the term "microtransaction" to mean "paid content". I think both are viable business moment for the industry to go forward - and the millions of people playing free-to-play, pay-for-items MMOs seem to agree. The "paid content" in the $5-10 range is not "microtransactions" IMHO, but the name stuck - they are price segmentation tools. Microtransactions would be a scheme e.g. in a RPG where you can buy "RPG points" in the console "OS" with "real money", then inside the game itself buy health potions for $0.10.
User content is FAR from impossible for DDR, GH, and RB. There are similar open source games or even the games themselves where users have created content. All you simply need is an editor and really one for such games would be really easy to create and use.
Have you tried them? I had great hopes for Frets on Fire, for example; it turned out to be somewhere between "exactly the same as Guitar Hero, but without all that
fun", and "complete crap", depending on what songs you try. It's a monumental failure of user-generated content, for all the reasons that will make any kind of easily copyable content crappy in the hands of users. In GH games, you have basically three files for every song: the background music, the foreground part (which you are supposed to "play") and a chart with timing which says what button you need to press in what specific moment in time so that the game will mercifully play you the foreground part instead of a random jumble of "wrong!" notes. Needless to say, there's a considerable amount of skill required to make that last chart; skill which has obviously not been present when the Frets on Fire songs I tried were created. To take things from "not fun" to "complete crap", most of the user-create songs for Frets on Fire hadn't bothered with separate "band" and "guitar" parts, just copying the original piece of music twice - which means you hear exactly the same no matter if you play right or wrong.
Well you wouldn't *necessarily* have to share the tracks, just the control data. The problem would then be to ensure everyone can get their hands on the same copy of music so that it's not out of sync.
See above: you need a separate recording of the guitar and everything else, so it's not just the control data.
I am extremely prejudiced against user-generated content, because since 2002 I have shipped four PC RTS games with a very decent, user-usable editor (which was definitely not trivial to make), which reached a combined user base of well over a million. I've written documentation, I've answered countless editor-related questions on forums, I've supported wannabe content creators over IM. For these five years, I've never seen a single
decent map for the games in return. 99% of the users simply give up once they realize it's real work to make maps, not something you accomplish in 15 minutes; the rest of the 1% release maps which are basically random generated maps with a ton of their favorite units scattered around the initial player positions.
There are talented, focused individuals able to create valuable content, as Counterstrike and DOTA show - but they are statistically insignificant numbers, so unless your game is not just well sold, but a megahit, there's virtually zero probability that one of them will grace it with his efforts.
A solid system of paid downloadable games and content for games
and users who have learned to accept this arrangement will not only help the traditional $60 retail games stay profitable, but will enable smaller studios to invest less and still see returns. There are really only two price points for games on Xbox 360, for example: $10 for Arcade games, and $60 for retail games. I'd like to see the whole range from $0 games (with paid items etc.), to $10 for Arcade games to $20-30 for smaller games (without cinematics, voiceovers, three multiplayer modes and a collection of ponies) to the $60+X retail games (plus collector's editions, downloadable maps etc.). This will allow a much greater freedom for developers to decide where to place their efforts to make the best game - currently you are in danger of being killed by reviewers if you don't have all of the features of all the Top-10, tens-of-millions-budget titles of the last 6 months.