The only reason I can think of is that it's to be some sort of barometer on how over or undervalued we are, but I don't think it would be a useful one either way. For HNWs who don't want to deal with the exchanges, there is already SecondMarket, and we can see how much is bought there. And really, if they cannot gather any more coins from larger OTC miners/sellers, we probably would have noticed after some time. Regardless of how crooked the exchanges are, given some time and collectively, I do believe they are representative of supply and demand and interact with OTC.
So my guess is there's just nothing else big happening and people are looking for some meaning to the price movements again.
Which trendline, the one from 340 (Bitstamp)?
Hardly a long-term trendline I'd say, more medium term.