I wouldn't call bitstamp a small exchange--smaller than mtgox maybe, but I would guess it's an easy #2, and it's definitely a more responsive platform, and if I send my sepa transfer in the morning, it's in my account the next morning.

edit...just saw the volume figures, mtgox, 54,181 (I assume that is per day), bitstamp, 6641, so much bigger difference than I realized.  Still, almost $1,000,000 per day I wouldn't consider small.

Anway, on that issue I posted about--it seems to have something to do with the "Instant Orders" as opposed to "Limit Orders."

The instant orders are completed so fast that they may or may not show up as "Last Price."

Still weird, like right now, tons of instant trades at $135.89 showing as the last price but the ask is just $133.89.

But trades are happening every 2 to 4 seconds, so I guess that would stress any system.

Also, yesterday I had a buy in at $131 that was completed to my surprise because I was watching the prices and no trades showed lower than $133.50.