The latest New Yorker cover was created by Bob Staake using Mac OS 07 (released in 1991) and Photoshop 3.0 (1995). You can watch him create the cover (and check out his unusual drawing style) here: 
Which begs the question — who needs CS4? And when does technology become truly obsolete?
At the non-profit for which I work, we asked the same thing. Yes, there are a couple of neat things in CS4, but overall it’s a very expensive price to pay for a tool that does pretty much what our existing tool does. I suspect in this financial climate, many businesses and non-profits are asking the same. This video sums it up nicely: the old tools are just fine. Maybe CS5 will have some must-have breakthrough?
Businesses always have to ask for the justification for a software upgrade. As a graphic designer at a newspaper, I’ve worked with Photoshop 3.0 to Photoshop 7.0. For illustrative designs, the gee-whiz factors of Photoshop are nice but not always essential for how we are able to do our work.
The bridge between upgrades of Photoshop aren’t as far reaching as the impact between upgrades of say…Flash.
So far, the only element of CS4 I’ve seen worth upgrading is indeed Flash. It may be true of the other formerly Macromedia products as well, now that they have the increased requirement of playing well with the rest of Adobe products. I should think the video producing elements would be rapidly developing to keep pace with the rise in UGC vids. I was a tail end purchaser of CS2, early of CS3 and am skidding to an abrupt halt at the thought of upgrade number 3 in as many years. Had I not been a student during this time, I could not have justified the additional $$. Especially, upon reflection of this article and the direction we SHOULD be heading post OLPC towards lighter weight software…where do I find a copy of PS 3.0? Hah!
-randa