rock band, guitar hero etc.

[Iceglow]

To answer the question of what makes these games appealing we must first boil down the games to the purest essence. In essence what Guitar Hero and Rockband both are, are merely rhythym/time puzzle games, piece together the notes in the right order at the exact right time to produce the music you are playing. Merge in to this the game Singstar which had huge popularity especially in Japan where Karaoke is extremely popular and you have a great marketing ploy. If people ask where the market for such games could be well look around next time you're in a game store and see:

Tetris - the original rhythym/time trial based game essentially control the blocks to avoid towering too high and losing the game within the alloted time limit.

Mr Driller - drill down through the ground to a set depth before air runs out or the precariously balanced bricks above crush you.

Columns/Gems/Any number of tetris rip offs - read tetris desc.

Brain Training - Complete challenges in a time limit, the lower the reaction time of the gamer the faster they'll get it right the younger their brain is.

Bomberman - heck do I need to keep on, we can throw silent bomber, and a whole host of other puzzle/simulations/arcade games in on this list too.

Basically, people like challenges, challenges keep us entertained because at heart all people are competitive whether they're a fat loser with no ability to compete at anything else or a jock who has it all we all wanna compete. Guitar Hero and Rockband basically provide people with a chance not only to compete with each other but with themselves, people get sucked in to managing to complete the game. Also to note to complete a song on any difficulty no one can tell you how to get better or how to do it you can't read a FAQ or a guide or a Brady games book. When youre good at GH/RB you're GOOD it is 100% skill based some people never move above easy, some master expert the fact is you have to learn to gain skill to do so. I have never seen anyone pick up the control and play anything through to the end on anything other than easy first time and even then most people fail horribly because even with the tutorial in game they're just not expecting it.

Edit for WK: Guitar Hero IV was released as Guitar Hero World Tour, the Aerosmith game was made from the exact same engine as Guitar Hero 2 even though Guitar Hero 3 had been released. Guitar Hero Metallica was made from Guitar Hero World Tour however so it could incorporate the various other instruments apart from Guitar and Bass. Ironically, Guitar Hero got steadily more difficult as it progressed to Guitar Hero 3, however many players commented that Guitar Hero 3 was in fact TOO difficult and had become less enjoyable, I think much of this came from Japan where they often play games more but in a more casual way noticable by the inclusion of very easy modes and european extreme modes of game difficulty found in other game series, Normal in the west is often the Hard settings in Japan. All of this means for Guitar Hero World Tour and onwards they toned the difficulty way down, in fact by the time you Play Guitar Hero Greatest Hits (also on the World Tour engine) Through the Fire and Flames by Dragon Force is particulary easy to see how different it is from in GH3 and it does play much easier, On GH3 I have a lot of difficulty playing songs on Medium still where on GH World Tour onwards I find it not necessarily easy but considerably more comfortable to play on Medium but then I hardly play my 360 atm let alone GH.