Basically they stick their finger in your butt and wiggle it around.
I skipped mine too. Or rather, I performed it myself.
I just checked on mysubaru.com:
replace engine oil
replace engine oil filter
inspect disc brake pads and discs, axle boots and axle shaft joint portions
inspect brake lines, check operation of parking and service brake system
inspect clutch operation
inspect steering and suspension
And that's it.
Spark plugs are supposed to be good for 30K miles, but if you've still got the factory Champion plugs in there, yank them NOW!

Put the NGK copper plugs in and change them every 15k or so.

I do and it makes my car happy.