to be fair, pingdom isn't going to supply you with details about cpu, bandwidth, disk, memory, etc usage for a multi-node deployment - they'll just tell you when its down.
i do think the prices are high, and you could certainly go it alone w/ nagios et al, but cloudkick offers a capable and detailed monitoring infrastructure that plugs into many outlets out-of-box. thats pretty cool if you ask me.
Yes, I am very excited about the new features, but they've priced themselves well outside what I'm willing to pay. If the host isn't down, I can ask nagios for free. If it is down, Pingdom (even the free version) will send me an SMS. There may be a target market for their price point, but I'm not part of it.
i do think the prices are high, and you could certainly go it alone w/ nagios et al, but cloudkick offers a capable and detailed monitoring infrastructure that plugs into many outlets out-of-box. thats pretty cool if you ask me.