As many of you have already stated, having players play their "true" age group should not be viewed as a problem. I think it is a great option for these players to play "up" when possible and/or play "age appropriate" when possible. These girls want to play all the time anyway, so why limit when they can play?
As Generik states, the teams that used 03 players that are normally rostered to 02 teams will not be able to play with multiple teams next year. I am sure there will be an 04 or two that could be invited to play with an 03 team during the Olders weekend, but time will tell. I don't know how many 03 players played this weekend that are playing on 02 teams, but the two players I saw play with Blues and the two with Arsenal are difference makers. As long as guest players do not take away playing time from the "normal" team players, I am all for this practice.
Lastly, congrats to Arsenal on the finals win. That is a great team. I think many teams could have won the title and we all would have said, "yeah that seems right".