Bagpuss said:
D20 Modern provides very, very little for Sci-fi gaming, psionics and thats about it, no spaceships, no laserguns, aliens, doesn't really provide enough even for an X-files campaign. Let alone Stargate SG-1 or something like that then the GM will have a lot of work to do....
...Its only really worth buying because its a familiar rules system. There are plenty of equal good generic systems. I can't see the big selling point if you happy to use a system other than D20.
Just needed to chime in here on a couple of things.
1) It does have enough for an x-files campaign. I cannot think of a single element that it is missing for such a campaign. I would guess x-files was one of the things the authors had in mind for running such a game (in fact, I don't need to guess, Skully and Mulder are mentioned by name on page 299). You could do an x-files game right out of the box with this system.
2) I am working as fast as I can on converting d20M to a StarGate SG-1 campaign setting. It's going to be neat. However, I still have 2 seasons of episodes to go before I am ready to put pen to paper (well, fingers to keys), though my notes are pretty damn extensive at this point, and I can already tell it is going to shape up to be a nice setting that works very well with the d20M rules. I know of no other system that is being converted actively to a StarGate campaign, which brings me to...
3) There is one HUGE reason to pick up the d20M book that I think you are forgetting. This is only the first book. There are a ton of third party, and WOTC, products in production right now. This is likely a long lasting game that will have very good support. Saying "there are no rules for x,y, and z yet" is like complaining about the 3rd edition player's handbook's lack of monsters and magic items in the first month it came out (which it had, but only in a small amount). There will be lots of sci-fi support for this game. In fact, there is already more sci-fi support scheduled for this game than any other d20 product I know of (and more than many non-d20 products as well).
Just give the game a bit more time than three weeks to judge the entire system as lacking the details you want. It's not done, it only just started. A lot more is coming out for it, and I think you will be pleasantly surprised by the quality and diversity of support for these rules over the next year.