Until the introduction of personalised search my CTR decline had actually stopped and was rising slightly witnessed by my best month's earnings of 2009 in November.
I knew December would be a fickle month and being realistic I don't feel I'll be able to make any definite conclusions until the end of January when many of us will have seen much more "normal" figures. FWIW my actual traffic and earnings have halved in the past few days, my CTR has now stabilised and I really do not expect much now until the first week of January.
As a point of interest, and I know it's been discussed in-depth on the search forum, it seems a bit crazy to me that I have specialised widget sites and users visit them, I assume, to learn about those products and I do not think it's unreasonable of me to expect the ads being shown are about my widgets.
Does anyone know, or has seen, whether their widget site(s) are displaying off-topic personalised results?