Ok so doing a routine check under my hood and saw this.... Any Ideas/suggestions before i take it to the mechanic? it's an 05 sedan MT 131K miles.
I've also been getting the worse possible gas mileage.

its hard to tell from the pix, but are you getting blowby through your plenum bolts? if so, loosen, then re-torque all of the plenum bolts using the pattern in the FSM. also, the bolts you have on there don't look like they have much bearing surface - throw some small washers under them if you don't already.

Could be an oil leak, possibly the screw could be either too loose or too tight. But to be safe I would take the car in just in case.

It's hard to believe you have that much blow by even with the amount of mileage on your G. I've never seen oil sitting on top of plenum bolts, even the wrong ones. Try torquing the plenum bolts but also check your PVC valve, is it plugged up? Also check the hose a lot of oil passes thru there. Is the plenum the only place you find oil?
Gary

Looks like oil was spilled on your intake. Just a drop or two will spread like that in no time. If your not losing oil, don't worry about it.

Thanks for the feedback, so far i'm only finding it here but i'll continue to look for oil else where.