As a set-collector, that's supposed to irk me. And it has in the past. Very recently, in fact (see: 2006 Alex Gordon, etc). But not anymore. As of now, I'm done with that.
No, I'm not dropping Topps. I will continue to collect Series 2, and when I receive all of the cards between and including 331 and 660, I will be done. My set will be finished and there will be no agonizing here or even in my angst-ridden brain over the "missing" No. 661. Topps 2010 is a base set that features cards No. 1 through 660. Period. End of story. No epilogue. No sequel. No man behind the curtain.
If you let it bother you, it will. And in that case, I suggest going all vintage, because there is no use in venting at a modern corporation. Have you seen what passes for business ethics today? There is no hope for these people.
Meanwhile, this is just another example of focusing on what you have instead of what you don't have. This kind of thinking is still a work in progress for me. But I'm really trying.
And along those lines, I dug out some No. 661 cards that I DO have, back when ol' 661 was a cooperative, card-carrying member of the base set. I know you have some of these. Take a look at a few. Maybe it'll help quiet the screaming voices.
#661 - Chris Hammond, 1993 Upper Deck. OK, I know Upper Deck is not part of this particular issue (I wonder what they would do with this Strasburg fellow), but I just wanted to show all of the teal. Isn't it soothing? Remember when people wore it because it was fashionable? Remember "Whoomp! There It Is?" OK, sorry, not soothing anymore.