Snow Leopard is available for distribution tomorrow. After reading initial reviews of the latest Apple OS, I would say it's a recommended upgrade for Mac users using Intel machines, especially photographers who demand a little more from their computers. I have a few notes for those of you thinking about making the move.
First, read Jason Snell's excellent Review: Snow Leopard. He's been working with the software for some time now, and he does a great job of showing us the ins and outs of the new OS.
If you're a Photoshop users (CS3 or CS4), then you should be hanging out at John Nack's blog. John is addressing Photoshop compatibility running on Snow Leopard. There's lots of good information there. As far as I can tell, Lightroom should also run fine on Snow Leopard.
Aperture and iPhoto users should have a smooth transition to Mac OS X 10.6. Apple is very good about taking care of their own, and users should have a great experience with both applications.
If you want to save a few bucks, you can buy Snow Leopard on Amazon for $25 instead of the regular $29 price tag. Family packs are available too.
BTW: Amazon notes on the Snow Leopard product page that Tiger users must buy the more expensive Mac Box Set that lists for $149 on Amazon and includes the OS plus iLife and iWork. But in Jason Snell's review, he remarked that Tiger computers will boot from the upgrade disk. I'll report more as soon as I test myself.