For 2004 rear wings will have the number of elements reduced. Currently front and rear wings have a limit of three elements (plus one extra lower one for the rear wing). I understand the new rule will limit the rear wing to two upper elements. I do not think it is allowed for the teams to substitute an extra upper with the lower element.
For 2005 and beyond , The was talk of the teams being forced to run a low downforce (Monza) wing for the full season. Also there was a suggestion a standard wing for all teams or a homologated wing per team per season.
Scarbs...