pf and route-to rules

Hi all,

I can't for the life of me get any "route-to"
rules working with packet 
filter.

i.e

"pass in on fxp1 route-to (fxp1 $host) inet proto tcp
from any to any 
port 80"

This to me implies that any traffic coming in on fxp1, port
80 should be 
routed to $host ?

Am I correct in this assumption or do I have it all wrong?

Cheers,
Linden.