Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of GT Solar International (Nasdaq: SOLR) are having a moment in the sun today, jumping as high as 10.8% on more than double the average trading volume.

So what: It may be earnings season, but this GT Solar's jump comes from a different background: a Chinese LED systems specialist just placed a $219 million order for LED-producing tools from GT's catalog. Curiously, a $94 million order for solar-panel production tools failed to move GT's stock at all two days ago.

Now what: To put that order into perspective, GT saw $135 million of revenue in the July quarter of 2010 and $263 million to close out the calendar year – so this is a big one. One word of caution: As shown by a gloomy pricing forecast from Cree (Nasdaq: CREE), the LED market might already be oversaturated with overly-efficient manufacturing equipment. The Chinese market might stand apart from the global trend to some degree, but LED-making equipment sales could come to an abrupt halt in the near future with terrible results for GT Solar and Veeco Instruments (Nasdaq: VECO).

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