Sounds exciting!
I too received a bimac, I've had him 3 weeks today. (I've been meaning to post and start a journal, just work has been killing me!)
He's been spending most of his time in his PVC den, closing himself in with clam and hermit crab shells. He sometimes comes out at night and hangs out on the side of the kritter-keeper.
He seems a little more social with me now; he doesn't run and hide every time I enter the room. Before, if he was out of his den, he'd dart back when I entered the room. Now he'll continue to hang out, though he may darken or flatten out.
On Wednesday he was out and I opened up the 'keeper and put in a hermit crab for him. He didn't run and hide, which is a good thing, so I'm hoping to get that connection that seeing me = you getting food.
Last night he was hanging out as well, so I put in a big hermit crab for him. He jumped on it right when I let go of the shell. The octopus did ink twice though (the first time he's inked when in his critter keeper). I don't know if it was because of me (like I said, he's never inked before because of me), or because the hermit crab didn't want to be eaten and was putting up a fight. (I sucked the ink out pretty easily with a turkey baster so it wouldn't pollute the water, before it could even reach the skimmer).
I'm hoping within the next week he'll be eating out of my hand as well. I think he's getting ready to go out into 'the big tank' and stretch his 8 legs a bit.
-Warren