The change doesn't make things perfect, however. T

The change doesn't make things perfect, however. There could still be orders in for less than 5000 (or whatever the minimum tier size is), or "All or None" orders placed that won't even show on the Level 2 quote. Also, one very common misunderstanding with Level 2 quotes is that the bid/asks that are showing are representing the only orders there are. This absolutely isn't true. Remember, the only ones showing are the highest bid, and lowest ask for each market maker. For example, if NITE (a very common MM on penny stocks) is showing an ask of .10, they could also have customer limit orders to execute at .11, .12, .125, and down the line.