We all grow and learn from others success - i think it will make us more successful.
Sometime we may think that a competitor/other company progress is bad for our company. I don't, at the end of the day, any progress that happen in the startup world had a direct connection to other startups success.
The more that we help others to succeed, we grow ourselves and make us more successful.
Look at investments for example, the more startup will succeed, the more investments will come, when and internet startup will get an IPO (FB, twitter ...? ) then more VC money will come, more money will be direct to the industry, attracting better people, create new initiatives, adding new angle investors and provide to the end users more selection to choose from, ultimately adding more consumers to each industry.
here is a small example of how i promote Balsamiq Mockups (Balsamiq page), note that this video was seen by almost 2000 people, i hope it added new clients to Balsamiq :)
So Smile to the world, and the world will smile to you, help others and they will help you....circle of life.