Internet marketing is a very broad subject. In my opinion at its simplest level it is about:
-campaigns that drive visitors to your web site
-how well your web site does in terms of conversions & user experience
-your ability to measure & analyses your performance so that you can improve both your campaigns and your web site
To date many consultants and service providers focus on one particular aspect of internet marketing. Either driving traffic, or improving conversion rates, or helping you measure and track visitors to your web site or blog. To effectively manage the internet marketing of your web site I believe that one needs to take a more holistic and iterative approach. This is not a simple task; it requires a host of skill sets and tools.
One need would need to have analytics set up on their site (like www.omniture.com) so that they can measure and analyses the current performance of their website and campaigns. Then you will need to have someone who can review the data to determine the ROI that is being achieved by your marketing efforts, the conversion rates of your different success events and where you are losing visitors.
This analyst should have knowledge of marketing and usability, or be a part of a multi functional team who can come up with alternatives to try and improve the current marketing efforts and the user experience of the site.
These strategies will then be handed off to a design and development team or provide to the agency who implements the campaigns or manages the site.
To properly measure the impact of the changes you should take advantage of multivariate or A/B testing so that you can clearly identify the impact of the changes that you have made.
Then the process starts all over again with review the results…
This is an area that I am currently working on. I'm trying to tie together our current service offerings into one holistic internet marketing service. It will take me some time to solidify how we will offer the service, how we will position it… but it is an area that I see huge potential for people to see measured improvements and know what is happening with the money they are spending.