We are currently doubling the support staff at MtGox and should have new staff hired somewhere in April (hopefully), but I though it was worth sharing some numbers.
Please make it possible to grab the order-book more frequently than every 20 minutes.
comboy who maintains
http://bitcoinity.org/markets tells me that there's a 20 minute limit on downloading any book from mtgox, which is why only USD shows the full book there (as I understand it also getting EUR book would mean that both EUR and USD would have to be 40 minutes delayed). This is a silly limit imho.
Solving this would only be a matter of buying and setting up more computer hardware. Please do so.
If this is correct, I can only second this. What about being able to fetch the entire orderbook only once pr 30 mins, and then for the rest of the time, it's possible to fetch diffs to that ? Forgive me if this is already possible and I'm unaware of it.