Target Audience is the users who will best respond to your brand.
Who was this product made for?
Who's best to drive the most revenue?
For example, Box launched their product initially for anyone who wanted to access their files from anywhere. Their founder Aaron Levie soon discovered that a product like this was missing in businesses and knew more revenue would be generated from business then consumers. The product itself shifted to be more collaborative and network based and so did their marketing strategy. Find out more about Box and Aaron Levie on this latest article from PC Mag.
Be more specific, but not too specific.
Consumer targets can be defined by several different aspects such as demographic, hobbies/activities, education, etc. as they should be. Consumer targets are vast and if not narrowed down millions of dollars can be spent trying to reach a user just once.
To quickly elaborate on that last point… as said earlier, consumer targets are HUGE. Everyone can be a consumer, but not everyone is in business. Narrowing B2B targets too far can get expensive, create creative burn-out more quickly, and make the data statistically insignificant.
When should each target be used?
Start with the decision maker because they're ultimately making the purchase. If this user proves hard to crack or needs coaxing layer in the IT Professional, but make sure the campaign aligns with this new, very different audience. Decision makers want to know this product is going to increase revenue. IT Professionals want to know how easy the product is to install and get end users to adapt. Decision makers read Forbes. IT Professionals read TechCrunch.
If including the end user in a campaign, focus messaging on productivity. How is this going to save time and help users complete their real work. Also, this is a broad audience. Anyone can be an end user. Site & placement assignment can be much more broad and less expensive, however they're not going to drive revenue up front. They'll download the free trial or check out the video, but then they'll need to climb their internal corporate political ladder to convince the higher decision maker power. So, when asking end users to get involved be prepared for a long wait in your revenue pipe line.