47 people clicked through to that post from Facebook. 5 from Twitter.
The 5 from Twitter all did so within an hour of the post going up.
The 47 from Facebook did so over the course of the following 12 hours (19 of them within an hour, but then an ongoing curve downwards).
Which indicates to me that Facebook does a pretty good job of knowing when something is interesting to my friends, and keeping it "active" for a while, whereas Twitter sweeps it away near-instantly, and unless it really grabs people it's gone.
And looking at my overall referrer stats, Facebook gets between three and six times the number of clicks that Twitter does.
(Just had a look at my actual LJ statistics too - yesterday I had 145 readers, of which 100-ish were reading via their friends-page and 45 were going direct to my posts/journal. Sadly I don't get the same info from DW, but Google Analytics tells me that 78 people visited that post on DW.)
Original post on Dreamwidth - there are comments there.