Call me naive, but I just don't buy it. ETMM and NITE trade how many thousands of stocks, ETFs, etc on the NAS, NYSE, AMEX, OTC etc?
There's no way they all have people who are familiar with every single stock and try to manipulate it. The only way it is possible is through automation (which, I guess, is fairly plausible.) I just think they have bigger fish to fry. It seems to me they'd make much more money on the spreads of high volume big board stock than mucking around in a low volume penny. I'm opened minded however. If there are articles on MMs targeting specific pennies and how they do it, I'd be interested in reading.
I did see the multi-million ask this morning and it was bull. I'm more likely inclined it was an individual or group who is putting in phony orders (who is going to buy in a low volume stock when they see 15 million on the ask?) than the MMs themselves.