I really wanted to get one of the Acme sleeves, instead I bought a cheap InCase from the AppleStore when I picked up my 15" AluBook. I'm assuming that you only want a thin sleeve and not an actual case/bag?
Are they too fruity? Well it depends on the color you get (I think the patterns are a little too much for most guys) but I think it is really how you carry it. You've gotta love what you get and if you do, you shouldn't feel self-conscious about it. I'm a 21 yr old male at a fairly fashion-conscious university and I'd love to have the gold, black, eco green, gray flannel or the new leather sleeves. Those are my choices!