No longer are you required to have finished in the top 2/3rd's of
a category 2 event to be eligible to attend a Category 1 competition here is the
section from the 2010 (now out dated) Sporting Code:

3. 4.2 Additional requirements

A pilot has to have either:

• Competed in a Category 1 hang gliding event (excluding Women’s Worlds) in the
four years before the qualifying date,

• Or placed in the top 2/3rds of pilots in a Category 2 hang gliding event
during the 3 years prior to the Category 1 Championship.

• Or placed in the top 2/3rds of pilots in a women’s world championship during
the 3 years prior to the Category 1 championship.

Now the only requirement is that you have 20 WPRS points.

http://civlrankings.fai.org/?a=326&ladder_id=1

That would include a little over 500 pilots:
http://civlrankings.fai.org/?start_rank=500&a=326&ladder_id=1&ranking_date=2011-03-01&=