I took a look at the 2011 WOC sprint finals results, looking at the year each top 20 finisher first had a top 20 finish in a WOC final.  The darker shades indicate more a more recent first top-20.  The darkest blue are people who finished in the top 20 for the first time in 2011 or 2010.

You'll notice that quite a few people reached a top 20 in a WOC final for their first time at the sprint. Compared to the 2011 WOC middle and long finals, the sprints saw a lot of "new" names.