agree, sideways has historically always been bullish.
Not so: price went sideways around $14 for about a month, July 4th-August 1 2011, and was followed by a drop to $6 August 6th:
http://bitcoincharts.com/charts/mtgoxUSD#rg60zczsg2011-07-01zeg2011-08-30ztgSzm1g10zm2g25zvThat said, I agree that since the primary use of bitcoin these days is as a store of value, sideways should mean the market goes up. Investors don't need balls the size of wheelbarrows to hold on to their BTC through the daily rollercoasters. On the flip side, the google trends data indicates that money flow into the exchanges will likely be dropping as fewer new people hear about BTC, same as the slow drop during summer and fall 2011. But a strong buyer has been enforcing a ~$120 bottom the past week, yet whenever the price breaks $150, thousands of coins seem to appear out of nowhere and get sold on the exchanges.
With all of these strong and conflicting signals, for the first time in a long time, I don't have a good idea where the market is going in the next two weeks. Therefore, my guess is that it keeps going sideways in the $120-$150 range. It's a good time for an anti-volatility trading strategy: sell when the price is the highest it's been in the past ~24 hrs, and set a rebuy $3-5 lower.