I did this when my textbook startup was sent a cease-and-desist by a major textbook player for B.S. copyright infringement. I immediately forwarded the letter to the Harvard Crimson (Harvard was our biggest market), and they promptly ran a front-page story about us being sued.
The cease-and-desist said we had 10 days to take down our data. I never took it down and never replied, and never heard back from the company again.
Not only did the press scare them away, but as you mentioned, gave us a front-page story we couldn't have gotten any other way.
That said, I was very confident that their case had no merit and that they wouldn't take it to trial (or maybe it was that we were on our last leg and had little to lose).
Funny story: my next startup and all-of-a-sudden we're currently partnering with the company that threatened to sue me. I'm assuming they don't know it was me behind both companies!
I don't see how these two companies are competitors. Start2Cloud appears to be akin to a directory or online magazine centered around providing information on "Cloud" services from many companies.
GoodData appears to be providing some sort of data collection and analysis services.
GoodData would just be another company/service reviewed by Start2Cloud, no?
Never fun to be threatened of course but when you can use it to enhance your visibility, well that is kinda priceless.