Yes, that's exactly the reason for the tumble the past couple of months, even before Obama was elected. People who where in the know knew the fiscal was coming and rates may go up next year so they sold, a lot of people have had huge gains in this stock and did not want them possibly taxed at a higher rate next year when they sold.
IMHO though, I think the selling is now over because anybody unloading this stock for tax reasons has done so already more than likely. Why would they want to wait for the stock as it was drifting lower and loose more of the value on the stock? It's up from here, and look out next year when all these people who got out don't want to be without their apple stock and buy it back, especially after the great earnings they will be reporting with all the awesome holiday sales.