The ‘base’ standard wheel design on the new Cadillac CTS is one reason NOT to get a base vehicle:

2008 CTS standard 17" wheel

Or the machined version:

2008 CTS machined aluminum 17 wheel

In person the large round center cap reminds one of the old moon-type hubcaps.  Not a sporty impression.

The optional sport wheel looks much better:

2008 CTS painted 18" wheel

and the CTS sport high polish wheel continues the trend:

CTS Sport high polish 18 wheel

The new CTS-V wheels are similar but have some “V” action going…

2009 CTS-V wheel