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 optical networking gear maker Finisar (Nasdaq: FNSR) rose more than 14% in early trading after a Morgan Stanley analyst said in a research note that the company could take share from industry peer JDS Uniphase (Nasdaq: JDSU).

So what: Morgan sees the flooding in Thailand hurting JDS's business. Management confirmed as much in cutting its second-quarter revenue outlook by $35 million to $45 million. Investors ignored the weak guidance in pushing JDS shares up as much as 11%.

Now what: Of the two, Finisar is the one priced for less than the long-term earnings growth rate analysts expect. Does that make it a better buy? You tell me. Would you buy shares of Yingli Green Energy at current prices? Please weigh in using the comments box below.

Interested in more information about Finisar? Add it to your watchlist.

Fool contributor Tim Beyers is a member of the Motley Fool Rule Breakers stock-picking team. He didn't own shares in any of the companies mentioned in this article at the time of publication. Check out Tim's portfolio holdings and Foolish writings, or connect with him on Google+ or Twitter, where he goes by @milehighfool. You can also get his insights delivered directly to your RSS reader.

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