Traditional technical analysis for a wedge says you take the high at the start of the wedge (Dec08 - 0.9802) to the low of the first swing (June09 - 0.8399) and project that distance from the breakout point.
So if we breakout here around 0.8680 then the projected target could be 0.7277, which sounds wild but looks very reasonable on a weekly chart.
That kind of lines up with the 78.2 fib retracement from the 07 lows to the 08 highs.
I would expect a bounces at 0.8180 and 0.7785
I think a lot of traders have been looking at this chart. It might be the reason cable has been so well bid.