I accidently spilled some oil on the air filter while adding oil to the engine. No problem or should I replace the air filter.

How much oil are we talking here? A few drops? Half a quart?

Where that air is headed, there's going to be oil anyway, so even if some oil were to make it through the filter there'd probably be no harm done. I'm no expert, though.

enough oil on the filter will take out your MAF sensor and leave you in limp mode or worse

Probably spilled about 1/10th of a quart of oil. I have not driven the car for two days- just making sure the oil is all dried up on the filter.

Oil dries?

replace the filter, better to spend $50 vs. 10x that on fouled MAF sensors.

Chuck is spot on here... We can't even get away with lightly oiled K&N Filters without blowing the MAF and that oil is made specifically not to come off... The oil won't dry, your only options are a can of brake-clean to break it down and clean it off COMPLETELY, or simply replace the air filter. You don't want to suck it down onto your MAF... chances are slim but not worth the risk imho.

Note to board: Never follow my advice!

Thanks guys for the advice. MAF sensor? I guess I'll suck it up and by a new air filter and be over with it.