Forum Moderators: DixonJones
[google.com...]
There are other tools like Compete.com and Alexa.com but they information you get back from those services is very limited and often hard to use as they do not have a large enough base for numbers.
Paid tools like comscore and hitwise, while comscore does have some great data, its not cheap to get back out and hitwise well as I told the reps from hitwise "I would happily pay them to give our clients data to the competition" as the data they have for the US market is 95% in accurate and often just darn right silly.
While Google's tool is free, they out of all the companies have the most to loss by not having the right data, as the alorithm at Google for a long time now has been using the traffic to sites and a key metric (hence when you can see stats from back in 2007 yet the tool was only publicly available in 2009).
Google's goal is also to provide a better way to advertise, allowing even small agencies and individuals to make educated marketing decisions.
As for being accurate, I have access to stats from some of the worlds largest websites and the numbers Google gives back are scary in how close they come, while not all sites are dead on accurate they are close enough that when I am out of the office I'll check traffic patterns via Google rather then having to VPN in and check the logs directly.
Hitwise
Nielson Netratings
Comscore
Compete
Do some research around these.