There's a nice picture of the 330i SSG steering wheel in the latest BMW 3 series sedan catalog. (Ask your friendly dealer!) It's the page right after the Performance Package section. The same catalog has a smaller picture of the wheel and shifter both. It looks rather nicer than the SSG setup in the Z4, I think.
BTW, I drove a Z4 with SSG in the sport manual mode, and I didn't notice the problems that the Bimmer article talks about. The upshifts didn't feel as snappy as the M3's SMG, but they still compared well to my own shifting with a manual. Downshifts are amazingly good and fast. I plan to get one myself.
Paddles are a big improvement over M3, with forward motion giving downshift, back motion up. Left and right paddles behave the same. I much prefer the positioning and shape of the SSG (330i and Z4) paddles to the SMG (M3) paddles. (I have driven both.)