The first time I put AS Ceramique on my CPU (with heatspreader), I just made a line down the middle and put the heatsink on top (as per the instructions on the Arctic Silver website), but I was concerned that I had put too much on, as it was a little hot.
So I took it off and cleaned it up and followed the method given by Custom PC (a UK magazine), who recommended the spread a small blob with your finger in a sandwich bag method. Unfortunately, I found that Ceramique was a little difficult to spread evenly with a finger, so now I think that it's too uneven, as there seemed to be little bits where there was more TIM than others.
But, seeing as it's now summer, the ambient temperatures are fluctuating so wildly that it's hardly worth the effort to do it again, and almost impossible to tell if it's better with one method or another (difference of only 2°C or so.)
Basically, either I did both methods badly (which is very possible), or there isn't any noticable difference between those two methods if done correctly.