I suspect 10.6 will be a free upgrade from 10.5, as was done from 10.0 to 10.1.
Why should we pay for a stable OS? [...] i sure hope Snow Leopard is going to be free for those who purchased Leopard.
From your lips to Steve's ears! But I doubt it will be a free upgrade. I would be willing to pay some money for the update because I'm aware of the amount of time and money goes into programming. The past few OS upgrades have touted 100s of new features. If it's only a few new features, then I would expect a lower price because I'm (mostly) paying for what they should have gotten right the first time.
"New! Snow Leopard! Just as purrrfect as Leopard, but with all the sloppy code re-written and the major bugs fixed! Also support for Exchange that iphone users got for free last year! Also, support for that powerrrrrful intel integrated graphics chip we put in our $1500 laptops in 2008! Only $129.99! Don't forget, Vista is so expensive!"

Good points. This is why, if it is mostly maintenance with a few new features, I don't think it should be a full-price upgrade.
This won't be your typical maintenance release. Of that I can guarantee you.
I agree that it's unlikely that it would be equivalent to a 10.5.x release. It would be more substantial than that, but it's not sounding like as substantial as going from 10.3 to 10.4, or 10.4 to 10.5
We don't know the price points, or what new feature(s) there will be, and it appears the press release from the Canadian site was an oops since it's down now. So this whole thread is mostly speculation at this point.
If they offer a number of substantial new features or substantial under the hood improvements that significantly improve the OS, then I think a full upgrade price would be warranted. If they are mostly fixing what's wrong now and tweaking it so it's faster/more efficient/etc., then I don't think people should be expected to pay full price (maybe as a couple of people have mentioned, full price for new or Tiger users, half price for Leopard, for example).
With the dollar doing how it is though, by the time Snow Leopard is released, $129 might not be a whole lot of money anyway.
