Photoshop upgrade question

I have CS3 and I ordered the CS5 upgrade from Amazon. I f I download the trial from Adobe, can I just put the key in when I get it and be good to go?

I think you can.

Yes.
When you download the trial versions, and then decided to buy all you're going to get is the license/registration Key.

You shouldn't need to install the CD once it arrives, however there are some extras on the CD that I don't believe you get with the trial version that you might want to install. When you get your CD look in the Goodies directory/folder.

Definitely yes. That is exactly how I upgraded the last couple of times. I keep a spreadsheet with my activation codes so they are handy since you don't have a box sitting on the shelf.

The goodies folder contains some useful items like fonts but you can download all of this information from somewhere on the net.

Adobe was offering a discount to upgrade to CS5 when I was on their site today

Thanks for the replies, I was hoping that was the case. I got the upgrade for $139 on Amazon, so that was better than $199.

Just installed my CS5 upgrade (from CS2) this evening.

Early in the installation process using the CD, CS5 wants the S/N from it's package. Then later in the installation process the upgrade asked for my prior version of Photoshop and that prior license number. I had removed CS2 from my system previously. If you have registered your earlier version w/ Adobe, you can get the prior S/N from your Account area on Adobe's site.

The entire installation process only took about 15 minutes. And then the updating of the installation took a few more minutes.

Thread seems sorted, this is related
I have CS3 (legallly/ bought) and was waiting for cs 6 to upgrade, but adobe wants me to upgrade sooner to cs5, My cs3 was bought in South Africa (where I stay,) If I were to purchase (or have someone purchase me the cs5 upgrade in the USA or via adobe online) would the 'usa cs5' work with my "South African cs3" are there something in the product code that would conflict between the USA and SA version.
I know its not possible to buy with a SA credit card on the adobe US store, but would the software work with my SA copy, (I cant see that from $159 to $259 could be tax of $+-100 )
THANKS