I don't think the G-7 can make a trend, but it can steer a trend. The currency markets are huge as is the world economy. It is too much to expect a couple dozen movers and shakers can irrevocably determine international finance.
If the euopeans raise their inflation target (or scrap the whole inflation targeting scheme altogether) and the ECB lowers, then we will certainly see a drop in the euro. But that will be a short-term situation IMO. I think we could see 150 within a few months (or even weeks) of a move to 120 or lower. But that's just me, and I haven't even been able to time a stock trade right in 6 weeks ;)