The air turns crisp; the leaves fall golden to the ground. The neighbor burns those leaves against city ordinance, filling the air with the acrid but familiar smell of smoke. How best to complete the autumnal feast of the senses on this, the first day of fall?
By cranking up the iPod, of course.
When I think of great music for fall, I tend to look for some combination of these qualities:
- unusual instrumentation, typically acoustic and/or with some form of experimentation with sound
- lyrics that suggest or attempt profundity (results may vary)
- general mood that invites moderately depressive introspection
- optional: previous association with autumn, such as time of first exposure or significant live event
To get my playlist started, I offer these top three albums for autumn (plus a list of runners up), in no particular order:
Top fall track: Masterfade
Top fall track: I Wanna Be Adored
Top fall track: Oh Comely
Runners-up:
Wilco, Yankee Hotel Foxtrot | Elvis Costello, When I Was Cruel | Arcade Fire, Funeral | The Delgados, Universal Audio | Sufjan Stevens, Seven Swans | Sweeney Todd, 2005 revival cast | Betty Buckley, Heart to Heart | Jose Gonzales, Veneer | The Decemberists, any.
FilkBlog: The Scott Filkins Experience 
Granted, it’s not an album, and it’s much more mainstream than your picks, but “Wake Me Up When September Ends” by Green Day is one of my fave autumnal songs.
In addition to the obvious fall reference, it meets your profound/depressing criteria with lyrics like these:
Summer has come and passed
The innocent can never last
wake me up when september ends
and
here comes the rain again
falling from the stars
drenched in my pain again
becoming who we are
as my memory rests
but never forgets what I lost
wake me up when september ends