Aperture & libraries
You can export folder (in your example 2009) as a library. This self contained library can be stored where you like and once reattached it is very easy to switch libraries from within Aperture. The only shortcoming of this is that images from 2009 are only available when that library is open.
|Wood Panel Truck, Retired by Buzz Lightyear|
from Random Items - Challenge 22
|The Falls by jdaniels10|
from Show us LIQUIDS!
|Silence by JP Zanotti|
from Blown highlights