Ms can't be happy with that price drop. They get a bump of interest then it wanes. At the price and with the same multi-plats, good exclusives and a bigger back catalog it should be selling well above PS3 considering that unless you really want BR as well it offers essentially the same as 360 for a much higher cost.
If 360 drops back below PS3 (which it looks like it will) I'll be really curious what MS do then as if they leave things as they are then 360 will definitely be third in Others. I know some are assuming the current economic situation will favour 360 (and it should) but the crunch is already on and 360 is really only a small amount above PS3 and trending down from the initial cut vs PS3 holding pretty steady.
They better hope the price cut holds better in Japan and especially the US as a three to four week bump that settles back isn't much for a pretty big drop in regular price.
If 360 does drop back then if I was Sony I'd seriously consider a very modest price cut before holidays in Others. The way its holding steady even a modest drop would likely generate a sustained increase in average weekly sales, which tied to new games and holiday season should drive strong sales.