They are the new type AMG III, available in 17" (7.5/8.5) and 18" (7.5/8.5) approved for fitment to all C/CLK/SLK models. There's also a different type AMG III 19" for the CLS (as fitted to CLS55 models) and a 16 spoke AMG V as fitted to the SLK55. AMG V has only previously been available in 18" 20 spoke for the R230/W211.
2005 Alloy wheel brochure is due soon, so expect additional approved fitments and confirmation of the names of the wheels
Saw a new S Class in Stuttgart on Monday - there seems to be some more new wheels for that. The tyre size is slightly bigger than the outgoing W220 returning to a size like the W140. Cross compatability TBC. Anyone know the model numbers for the new S Class and R Class (same platform apparently, so same wheels)