I generally prefer silver, although the black is nice also.
My advice on this purchase: go with the v1200a plus II over the v1000s plus II. You will have a bit more room for your PSU and won't have to worry about this:
http://www.anandtech.com/showimage.html...iews/cases/lianli/pcv1000/largepsu.jpg
Why not? Silver is soooooo common!
Cars and PC's aren't the same thing. Plus, a Lian-Li case is not "silver" in the usual sense of the term because it is not a painted case so it isn't a metalic sparkly silver but brushed aluminum. The black is actually anodized as well, so it doesn't have a painted glossy look either and there is no paint to chip off. If you were going to make an analogy between a Lian-Li and a car it would have to be a DeLorean. Honestly, these cases are really such nice cases you really won't go wrong with either.
But the black will match more optical drives.
Lian-Li makes really nice aluminum bezels for both the black and silver cases, so you can get whatever drive you want (except slot loaders) and have it match your case beautifully... They are $10, but the case the OP is looking at is already $200+, so it's trivial IMO.