Check the "born on" date.....it's the #'s after the DOT on the sidewall. You don't want to get a 3-4 year tire that's been sitting around. I bought a Michelin PP for my 999 and it showed some dry rot around the circumference of tread near the side wall-where "chicken strips" would be. I had them pick it up and send another.
I've never gotten old stock when I've ordered tires (either over the web, or from the parts counter at a bike shop) But I've passed on tires that were in stock at my local dealer because of the manufacturing date on them.
I don't expect this to be any different, those large mail order houses sell a lot of tires. They should be fresh stock, but you can bet I will be checking the 4 digit code.