I'm fairly new to Oq and am probably not using it right. I go into it and find raids I want to be invited to and hit the wait list button. I can sometimes wait for hours without an invite. I'm a fairly well geared 553 warlock and am capable of doing pretty nice DPS. I'm trying to get into the 10 or 25 man heroic raids with no success. Never gotten an invite. Am I invisible? Do I need to "find mesh" each time I go on?

No, your ilvl is not sufficient to get you into heroic raiding for soo. It;s not that you are invisible, it that you aren't meeting whatever requirement the raid leader requires.

Heroics generally require around 570 to start

At 553 I would recommend more flex and to make sure you max VP every week to do upgrades. Ladyjay is totally right, that won't get you into heroic and I actually doubt that would get you into many normals (mostly because people have overly high standards but WE).

People are beyond moronic in their requirements for Normal/Heroic PUGs. It comes with not knowing the person's skill level/knowledge of the fights. Most of them can't even clear Heroic SoO, even after the nerfs.