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 Cree (NASDAQ:CREE) were shining brighter today, gaining as much as 15% after getting an upgrade to buy from research firm Cannacord.

So what: Cannacord bumped up its rating on the LED-lighting specialist from hold, saying its second-generation 60-watt bulb would benefit from a better cost structure and higher margins, and that further generations of the bulb would do the same. Cannacord also raised its price target to $80 from $65. Also driving the gains, rival Acuity Brands (NYSE:AYI) jumped as much as 8% after a strong earnings report this morning as it grew 13% and net income improved 35%, beating analyst estimates.  

Now what: The strong performance by Acuity seems to be a better indicator for the larger Cree than the upgrade. With 20 analysts covering the stock, the opinion of one seems to be negligible. Given that conclusion, today's bump seems exaggerated, and makes Cree's price tag harder to justify at a P/E of more than 50. Still, the LED industry seems to have a bright future ahead of it, and as a major player with an improving cost structure, Cree should have no trouble growing into its high valuation.  

Fool contributor Jeremy Bowman has no position in any stocks mentioned, and neither does The Motley Fool. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.