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 3D Systems (DDD -1.97%) jumped 10% today after coverage was initiated by an analyst.

So what: Analysts at Citigroup initiated coverage on both 3D Systems and competitor Stratasys (SSYS -1.95%) with a buy rating and giving them $60 and $125 price targets, respectively. They think the 3-D printing market could more than triple by 2017 as more manufacturers use the technology.  

Now what: Before getting too worked up about an analyst upgrade let's not forget that analysts have little incentive to get these calls right, as fellow Fools John Reeves and Ilan Moscovitz noted earlier this summer. With a trailing P/E ratio of 120 and a forward P/E ratio of 40, it's also important to remember that 3D Systems is also priced for a lot of growth in the future, so investors already expected this type of projection. Basically, I don't think an analyst call is a reason to buy the stock today and wouldn't change my investment thesis on 3D Systems or the industry because of it.