I tend to merge later and use the lane to near its full extent. After all, thats why the engineers built the extra pavement in the first place. It's particularly helpful in NC where there are three painted arrows indicating the end of an acceleration lane onto the freeway, so I tend to use that to the best extent possible.

(In VA and SC it's anyone's guess when the lane ends......)

One of the most infuriating things on the road is when people do not use the acceleration lane either by cutting across or not using the throttle. Worse, when people actually approach the end and hit the brakes. This prompts an immediate series of unpleasant words from me as I have to swerve or slam the brakes to avoid a now-nearly-stationary object.