Right now I am trying to find out merits and demerits of different ESB's in market. I tried to find out comaprison on google, but able to find only one, which is a paid :)
Can you please tell me the link to compare different ESBs available in market.
Be sure you want ESB......
"...an ESB is not on my list if the few "basic components" that I recommend for getting started with SOA. In fact, I discourage people from starting with an ESB. An ESB does not encourage good SOA behavior. ESBs are essentially integration systems, not SOA systems. SOA is about tearing down application silos, but integration systems reinforce those silos. "
If you are sure you want ESB then and you want proper analyst opinions on enterprise software then you are going to have to pay for it. I'm sure that a Gartner Magic Quadrant / Hype Cycle report first will get you a general overview. At the end of the day if you are going to spend serious cash on something like WebMethods, you should use analysts quotes to get yourself business backing.