if someone was getting those kinds of speeds we would start seeing the complete value, difficulty and everything else change completely
its a big jump but its expected, mining is profitable and people are sinking money into it, I doubt its any kind of government agency - BTC is getting big at a fast rate and this is the price we have to pay.
Price we pay? Guys, this is good for bitcoin. Makes us even harder to attack. It protects the value we have mined so far. Don't complain about new people getting in, they're helping the economy, spread the word and strengthen our security.
If difficulty was dropping... now that would get me worried.
I, personally, am not here to make a profit (I didn't even sell the bitcoins I would need to recover my miner cost), but am hoping to make the world a better place (however romantic/idealistic that might sound). Bitcoin is a money of (by and for) the people.