Past couple years I've flown maybe ~10-15 times on international flights, and never had any trouble. Last month I was down to Aruba, carrying gripped 5D3, 24-105, 70-200 2.8 IS II, Sigma 50/1.4, Sigma 14/2.8, EF 2x II, Kenko tubes, 430EX, D10, GoPro, chargers for all 3 cameras, big pile of memory cards (~200GB total), some ~20 rechargeable AA batteries, USB-camera-connection kit for iPad, etc. Nothing at the airport, as usually.
I think twice I've been swiped (for the bomb-detection device, don't know what they call it officially). About year ago arriving to Frankfurt, the x-rayed at arrivals. The border agent comes to me, holding my camera bag:
-You speak English or German?
-Which one you prefer?
-Either one, I don't care
-Is this your bag?
-There's quite plenty of equipment inside
-Yup (about same list as above)
-Would you follow me to inspections room
There he asked me to open the bag, swiped it with a rag, machine analyze for ~30 seconds, and then he let me go.