I feel the best way to illustrate the differences is through examples. Below is a brand experience video for the band Devo created by Mother Los Angeles.
The Devo site and film give off a wanky, dharma initiative vibe that is very distinctive and memorable. Although it doesn’t immediately discuss the product (music) it created a point in the mind of the consumer to make the gradual perception change of that music brand. It inspires the consumer to find out more and potentially purchase it; but, more importantly, it gets the consumer to continue using the brand if they liked the advertising.
Here is an example of a marketing micro-site for Clorox Whiten Your Whites.
The site is paired down to getting as many emails as possible, to the point that it ends up not feeling genuine or interesting. It shouts at the consumer a potential to win something if they give over their email (to be distributed Clorox coupons via email). Although the consumer may or may not use this product from the coupon, the likely-hood that they would be interested in learning more about future products is not likely.
In the end what is more important and effective, utility/marketing or branded/experience? Ultimately it would depend on the goal of the campaign/product; but, for any brand be it a band or a massive retailer, developing a long term relationship with a consumer will potential yield much higher returns and for a longer period of time.