a bit of their performance drop could also be related to actual performance drops during the christmas season...
http://rtmark.com/ has provided a place for dissenting people to get together, and one of the efforts has been to artificially slow etoys' servers during peak Christmas shopping times, making it seem that their site is too slow and perhaps driving customers off. If people see the site is slow and they're trying to buy toys on their lunch break, they're going to go somewhere else. Sales drop, stock drops. That's a lot easier to understand than all these "market factors" -- at least to technical folk such as myself.