Here's what Ars Technica had to say when 10.6 was released:

The final interesting group is owners of Intel-based Macs that are still running Mac OS X 10.4 Tiger. Apple shipped Intel Macs with Tiger installed for a little over one year and nine months. Owners of these machines who never upgraded to Leopard are not eligible for the $29 upgrade to Snow Leopard. They're also apparently not eligible to purchase Snow Leopard for the traditional $129 price. Here's what Apple has to say about Snow Leopard's pricing (emphasis added).

Mac OS X version 10.6 Snow Leopard will be available as an upgrade to Mac OS X version 10.5 Leopard in September 2009 [...] The Snow Leopard single user license will be available for a suggested retail price of $29 (US) and the Snow Leopard Family Pack, a single household, five-user license, will be available for a suggested price of $49 (US). For Tiger® users with an Intel-based Mac, the Mac Box Set includes Mac OS X Snow Leopard, iLife® '09 and iWork® '09 and will be available for a suggested price of $169 (US) and a Family Pack is available for a suggested price of $229 (US).

Ignoring the family packs for a moment, this means that Snow Leopard will either be free with your new Mac, $29 if you're already running Leopard, or $169 if you have an Intel Mac running Tiger. People upgrading from Tiger will get the latest version of iLife and iWork in the bargain (if that's the appropriate term), whether they want them or not. It sure seems like there's an obvious place in this lineup for a $129 offering of Snow Leopard on its own. Then again, perhaps it all comes down to how, exactly, Apple enforces the $29 Snow Leopard upgrade policy.

Guess they got it wrong too.