Hi Robert-
outside of some I/O pins for some basic smd leds......and some buttons input to make those leds do something..... I dont think any (but I'll have to review to be sure) 
your schematic looks similar to mine (I'll post when I get to work)..
but mine is missing the cap on the SD socket.. and I didnt do anything with AREF yet.. just using a cap and tying to GND is ok?
(I dont need to tie that to any voltage reference point? (ie: the 3.3v line at all?)
Lastly... (caps).. still a bit confused on these..
from the schematic,...it looks like ALL the caps used are polarized ones?? (or am I reading the symbol wrong?.. I dont see any +/- on the cap symbols anywhere?)
I thought the CAPACITOR symbol that had two STRAIGHT lines.. meant a regular old cap.. and a CAPACTOR symbol that had stiaght line and 1 rounded line.. was signifying a POLARIZED cap?
is this true? (or am I under the wrong impression?)
in this case.. then ALL caps used her should be polarized?
thanks!..
Oh and Robert.. the pcb design/layout is appreciated.. but when I show you the space and size (shape) of the PCB.. you'll probably just laugh at me! lol
thanks again!
we'll post when I get to work..and open things up again.