i think the hype that surrounds IG is more associated with its functionality rather than its looks. i agree that mappoint looks hella good in SD, but it's definitely not as functional as IG. personally, i would take function over looks any day. in my opinion, IG has better route calculations, POI database/search, updated roads (though not all), and better ETA calculations that self-adjust based on your actual driving speed. one of the things that drives me nuts about mappoint is that it uses the road speed inputs to calculate trip time instead of the actual gps speed. mappoint calculated the 5-hour trip to my parents' house as being 15 hours!!! anyway, i believe that the developers of IG take a good hard look at their end-user base and try to cater to their needs, to the point that they now advertise their software for CarPC's. though the IG interface is not as smooth or aesthetically pleasing, it is suitable for carputer/touchscreen use. unfortunately, they develop their software to be a standalone program, but so do all the other companies. but this is where the mp3car community comes together as far as integrating these things into frontends and such.
i commend the SD team on integrating mappoint into the interface, which i'm sure is no small feat by any means. while i think that the use of mappoint deters many people from purchasing SD, i don't necessarily blame the development team for choosing it. i'm sure there are issues of licensing, software modification, cost, etc... rather, i'm more inclined to blame microsoft for developing such a horrible program.