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 mobile multimedia specialist BroadSoft (Nasdaq: BSFT) jumped as high as 16.5% this morning on tremendous volume.

So what: A fresh telecom market report by analyst firm Dell'Oro notes that BroadSoft gained market share in the voice application server market during 2010. A similar comment in the same report about gains in a related market for voice-carrier hardware expert Acme Packet (Nasdaq: APKT) failed to light a similar fire under that stock, however: Acme is down 3% today.

Now what: BroadSoft has popped hard and often since its IPO last summer, sometimes on real news and sometimes not. The stock has now gained more than 500% since mid-June, squeezing out all but the most daring short-sellers along the way. With a P/E ratio of 220 times trailing earnings and a tendency to keep rising for no particular reason, such as on today's largely non-news, I'd be afraid to touch BroadSoft on either the long side or the short.

Interested in more info on BroadSoft? Add it to your watchlist.

Fool contributor Anders Bylund holds no position in any of the companies discussed here. Acme Packet is a Motley Fool Rule Breakers pick. 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 is investors writing for investors.