Warm greetings to all!
I thought I should post some kind of intro before I start commenting too much on what everyone else is saying.

I've been playing RPGs for 12+ years, most of that including Shadowrun--one of my first RPGs was a modified version of SR, in fact. I've been through three editions now, and while I admit at first I wasn't terrifically happy about some of the changes in SR4, I'm rapidly warming up to them--even planning to run a campaign of my own soonish. I've run SR (and other RPGs) before, but not SR4.
Most of my SR PCs have been magic users of one stripe or another--mostly shamans. (Sometimes this has caused confusion when I've played non-magical characters and start discussing the kind of magical countermeasures our targets are likely to have.)
Other RPGs I have played or run include GURPS (I'm running GURPS Reign of Steel right now), Feng Shui, Star Wars Saga Edition and the ubiquitous Dungeons & Dragons.