Originally Posted by Niki 
I think photolady is right, perhaps since you are using the honest to goodness, physical Adobe software you don't need the activation like you would if you downloaded the program from the website.
(assuming that's what you did, of course =)
I installed it from a disk I bought from B&H via a link on the NAPP website. No shipping charge.
While I installed it I also registered it. I think the registration page came up very early in the process. However, Adobe's website says registration and activation are two separate things so I don't think it was activated simply because I registered it
While installing, my computer informed me that the software was seeking access to Adobe (my McAfee AV has this feature). Once was after I registered and once again later. Perhaps the second time was an automatic activation.
One other thing. When I opened CS4 and clicked on Help, one of the options in the drop-down menu had the word Deactivate. That suggests to me that the program was indeed activated.
Richard