I know a lot of people who have liked the concept of Shadowrun since 2nd or 3rd generation (I'm one of them, I still have my 2e book). The setting is awesome, and while I think people who take their "real world characters" and toss themselves into a D&D world to try and emulate the idea of us dealing with a fantasy world is LAME (Gah I hate when I hear someone is going to run this cool idea blah blah, sorry, it might be superawesome if you like that kind of thing, to me, its lame, dead in the 80s, let the cartoon go ;)), I think the idea of "our" entire world being meshed with magic in some sort of post Mayan apocolypse to be very intriguing, especially with 4th edition where they've caught the technology up with our own and stepped it up a bit.
But why aren't more of us playing it then? I'm running a game over on the forums of dndorks.com (
http://forums.dndorks.com/forums/thread/810092.aspx) and one of the principal issues I'm having is the lack of GM support. A lot of sections vaguely tell you how to handle a particular type of conflict, but the core book doesn't do a very good job of explaining what are ideal difficulty levels, especially for a group of new players.
The next problem I have is related to the first, which is that there isn't an easy way to determine what is an appropriate challenge for characters with 0 karma, 30 karma, 60 karma, 100 karma, etc. I'm sure if you've played a group through 50 points of karma, you probably know what they can handle, but honestly I feel like there should be better difficulty tiers. I noticed the adventures often have whats called a Threat Level, some sort of system to describe who can handle what or how to modify the adventure appropriately.
But honestly, for someone like myself, creating a run by myself as a new GM to Shadowrun, I feel like I should be given a better idea of how to plan the run, what kinds of IC to use, what kinds of spiders, etc etc.
I feel like part of the reason is that Shadowrun leans much further towards "realism" in its rules, meaning that the system describes the rules as it is, rather than as some sort of gameboard for the players to play on. So if you know the typical stats for a large important matrix with its IC and so on, then thats what it is, even if it'll instantly kill your 0karma players... and thats fine, I suppose, it'd be lame if it was just as challenging to hack Ares at the start as it is 10 adventures later.
BUT shouldn't there be a way for me to know at what point can the group handle a run against Ares? Other than going over their large and complex charactersheets looking for every possible combination?