Ah, point and click adventures. I have incredibly fond memories of those games as King's Quest is the first game I remember playing (or trying to play). Sadly, they're pretty dead nowadays. True, they occasionally get released but they're incredibly obscure and, well, on the PC.
I think it's the slow gameplay that killed them. They had great puzzles but the time between those puzzles was just...painful (and sometimes even the puzzles were painful). They worked back in the 80's and 90's because point and click and RPG's were about the only games that concentrated on story and strategy. As the action, platformers, adventures, shooters, and every other genre evolved, point and click adventures started becoming obsolete.
Why would I spend hours rubbing every object in the game together trying to find the perfect combination when I can play Uncharted and get a better puzzle?
Why would I spend hours backtracking through screen after screen of walking when I can get a better story in Alan Wake?
Point and click adventures were great 20 years ago but they just don't really have a place in games today. Any game today can have just as good of a puzzle and writing. All point and click adventures had was those things and all the ones that dabbled in other areas just kind of failed miserably at it.
And a little off topic, but the next genre of game to suffer the same fate as point and click adventures-- the JRPG.
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All that said, it is interesting how these games can still find a home on portables and handhelds. I don't know if it's the cheaper development or what, but that's about the only place JRPG's and point and clicks will survive 5-10 years from now.
