The trendlines are color coded pairs. Each pair, consists of a primary trendline, and a secondary trendline at 1/2x or 2x the slope of the primary line (they're marked 2.00 and 0.50, the primary line is unmarked)
Of interest, the yellow trendline drawn between the Aug-07 low and the Nov-07 high, when GLD corrected it dropped down and tagged the 1/2 slope yellow trendline. It is likely that a correction from the current (or upcoming) high might follow the same pattern (the green pair of lines) At the moment it looks like GLD could push a bit higher, and I'll have to redraw the green set.
Also suggesting that we might be approaching a temporary high, are the normal chart indicators, the Stochastic, MACD and RSI are all more or less confirming the recent rally with no glaring divergences. However they do look like they are ready to turn down indiating at least a short term hiccup. The two volume based indicators (bottom two) are weaker, the Volume RSI is starting to fade as is the Money fFlow.
The 101 day cycle (yellow) is a major interval over the data set I have, hits in mid May.
The 50.5 day (blue) is midpoint of the 101 cycle, typically it woulod be considered more bullish if the trading high comes to the right of the midpoint. This CIT point is today (Wed 3/5) and could be a reversal of the little correction so far or nothing significant at all. I'm viewing it more as a location than a timing spot.
The 147 day cycle (red) has been important in its past incarnations and is due to hit mid month.
The 29 day cycles (orange) are the short term trading swings and tend to vary a bit between 27 and 34 days.
Given the current excitement about GOLD, I have a hunch the mid-March cycle point may be worth paying close attention to. If GOLD (and GLD) continues to press higher towards $1000 then I would expect the mid-March point to be the start of a sharp correction (15% to 20%). On the other hand, if the current weakness accelerates, then mid-March could be a low point. In either case it is probably a bit late in the game to be initiating new positions unless one is very disciplined about money management, use stops please.
Longer term I remain bullish on the precious metals with the same wild guess target I've had since the lows, $2500 gold is coming, I just don't know when.