I do not know about others, but on my machines Photoshop CS2 does not run in the 'Aero' theme and Illustrator has issues with some of the pallet titlebars (some are Aero and others are Basic).
Based on the posts in the Adobe forums, it appears that there are different issues being experienced by various users. This being said; the patching would probably require significant resources on Adobe's behalf to fix a majority of the issues. With the release of CS3 so close and the fact that Adobe's creative suites are considered by many to be the 'industry standard', it is not a real surprise that they have opted to focus on supporting Vista with future products and offer free patches/updates to fairly recently released products only.
Photoshop CS3 definitely has a few nice features: non-destructive filters, a workspace layout that offers some nice pallet options, and the new Camera Raw 4 which has many requested functions in the dialog when working with Raw images. From what I have read, Illustrator also has some improvements - especially in the color functions.
With Adobe not rewriting CS2 code for the Intel based Macs, it would also seem that a balance has been achieved due in part to timing in the release of Vista, Intel-based Mac popularity, and Adobe's development schedule.
For my part, I will stick with running CS2 on XP until I can afford to purchase the CS3 product. Hopefully that will also coincide with some significant improvements in the graphic adapters and drivers to unlock the real potential of Vista.
Note - I have not seen any pricing information released on CS3 yet, but have seen some suggestion of different packages being offered at different price points for the various needs of both casual and professional users.