Is SEO worth paying for?

[goldentalk]

Given the recent trauma that Google has inflicted in our online world. What does everyone feel with regard to paying for seo -
And for those that do pay for this service - what do you look for in your provider and do you try to pin them down (and pay them) according to performance?
Is it worth it taking the trouble getting a SEO and paying for it or you spending hrs trying to come up with high paying keywords?
Does anyone truly understand Google's inner workings?

[subhakars]

Yes, I think paying SEO will definitely help us to get more traffic to our site. Otherwise we have to keep searching the net for hours and gather all the related keywords / ways to increase the traffic. However before appointing an SEO, we should go through their work and check how well they are doing. Otherwise we will end up paying them unnecessarily.