The Guardian Cub, unlike all the other Pet Store fare, is a single Bind on Equip item rather than a bound item sent to the mailboxes of all your characters. For hardcore pet collectors, this is a bit of a bummer as the pet is not automatically purchased for all of your alts. If you have 15 alts you want the pet for, better be prepared to shell out some serious cash. However, that isn't the sinister part of the little winged one.
Being Bind on Equip, the Guardian Cub may be traded or sold to other players. That means you can give $10 to Blizzard for the pet and then post that baby directly on the Auction House. In essence you can now purchase a "Guardian Cub's Worth" of gold directly from Blizzard whenever you so choose. Blizzard is now in the gold selling business.
So what does this mean for you? In all probability, it means next to nothing. Blizzard has implied that this will somehow cut into the illegitimate gold selling market and therefore also cut down on the account theft that accompanies the gold trade. Frankly, I am skeptical.
Gold sellers will continue to compromise accounts which means that they should be able to undercut the going Guardian Cub Rate. This means there will still be a market for ill gotten gold. Sure there may be a small impact on gold sellers, but is it really worth looking the other way as Blizzard starts selling gold in its subscription based MMO.
Frankly, I would love to see World of Warcraft can the subscription fee and go freemium. Until that happens, however, Blizzard's thinly veiled sale of in game power is rather disrespectful to its players. The Guardian Cub is a clever way to sell gold without causing inflation, but it also leaves no doubt that Blizzard is happily sliding down a hill they peered over the edge of back around the time of the Activision merger. I plan to stick it out and see what happens, but we sail dangerous seas my friends.