I have a different take on it.

I think what we are seeing here is large investors entering at a price point more advantageous to their bottom line.

Mr. Money Bag Investor strategy #1
1) Slowly build up a stash of 2000-3000 btc over the course of a couple of days as to not leak too much during accumulation.
2) Make sure to have around a large pool of USD ready in MTGox.
3) Wait for a general trend down, and hit the market with a 2000 btc market sell.  (causing the price to drop 5-10%)
4) Immediately place a limit sell order just above the new low you just artificially created.
5) Start the DDOS to disrupt regular trades. (easily purchased)
6) Watch the lemmings panic sell further forcing the price down.
7) Once a sufficient number of Sell orders are well below the previous starting price, issue your main buy market order (think 4000-5000 btc)

Using the above strategy, anyone wanting to enter into BTC in a big way can ensure instant equity.

Market manipulation like this is illegal in other markets, but not here.  Also, add in the small market cap and this is almost a guaranteed way to make money.