The RPC interface certainly is not the fastest. There is a C++ blockchain parser that someone wrote that you could base your system on. If you want a really simple and quick solution that depends on a central server: use blockchain.info's api. It can be queried for all txs regarding a certain address.

On another node I wrote a python script to parse through all txs in all blocks, does some calculations and stores everything back into a database - it takes a while but works fast enough. The biggest hurdle for me was that I ran out of network sockets since somehow bitcoin-qt or my python rpc interface never closed them - so I had to tweak some parameters of linux network stack. Other than that look ups and writes to my database were much slower than the RPC interface.

The price depends on the trades executed on the exchanges. So yes you could do arbitrage - if you can move your money/btc between exchanges fast enough

The idea is that the transaction fees will be much higher due to bitcoin being used much more than now.

The IP addresses mean nothing - it's from where the block got relayed to blockchain.info's node - nobody knows through how many and which other nodes it got transmitted before reaching that IP.

Joking aside. That is exactly how I would do a 'burn in'-test before shipping.
Also it would be great news if they finally got something running.

Take a look at these payout addresses:
https://blockchain.info/address/1NLg3QJMsMQGM5KEUaEu5ADDmKQSLHwmyh

39 solved blocks in the last two days -> ~13% of all blocks -> ~13% of the hashrate:

5.8THash/s... that is quite a lot.

Does anybody know which pool/miner is that?