I'm new to crib sleeping - advice? (a little long)

I've made several posts about my sleeping woes in the past.  Here's the summary:

-- LO has always nursed to sleep in bed

--We've been bedsharing full time for 6 months

--he's always fought sleep

--he's been waking up every 45 min for the past 2 months

--he started a nap strike a few weeks ago

I just went back to work in the evenings and DH takes care of LO at night.  When I got home the other night, LO was asleep in the crib for the first time (he always screamed in the crib).  DH needed his hands free to warm up milk and he put LO in the crib screaming.  By the time the milk warmed up (~5 min), LO fell asleep.  It wasn't an intentional CIO.  The past few days I've been wearing and nursing him down and putting him sleepy in the crib.  To my amazement, he's OK with it!!!  He slept 5 hours straight last night!!!  It's bittersweet because I love cuddling with him at night but it's clear that he sleeps better in the crib.  I bring him in with us in the morning. 

Just now I put him in the crib for a nap.  He fussed (not really crying, but fussing) and I let him do that for 5-10 min.  I'm not sure I count fussing as crying it out.  Then he was quiet and awake.  I really, really wanted to pick him up because I kept picturing what Dr. Sears said about babies just giving up.  He spent 5-10 minutes being quiet and awake and then fell asleep.  It usually takes me 20 minutes of lying down to fall asleep so maybe this is what he's doing.  For those of you who have crib sleepers, is this typical?  Does LO take a while to fall asleep on his own?  Is fussing the same as crying it out?  He's sleeping so much better so I have to think this is good for him.