If you use any sort of RSS feed aggregator (such as Bill's LJBP list, for example) or if you read both 0xc0debabe and /dev/null and have a good memory, then you probably realize that Layla and I almost always post at around the same time.
The biggest reason for this is that we both post at-least-daily, and so when one of us posts, it's usually a good idea for the other one to kick out a post, too. We've got enough going on in our lives that if we were to post individually, we'd probably blow whatever remaining time we have each day waiting for the other one to get done with the posting.
Occasionally we run into problems where we both pick the same damned topic to post about, but we also usually try to talk about post topics beforehand and that tends to ensure that we talk about different things. I realize that it's astoundingly exciting to read about exotic things like how many fires we have in our fireplace once, but I could only imagine the rapture with which you'd consume this sort of thing again. Layla and I make sure our post topics are different in order to save you from such joy.
Anyway...since we're posting simultaneously, we can't be using the same machine—and for purely practical reasons, I usually use Layla's computer and she uses mine...which I think is pretty funny. Especially because Layla's computer has the awesome LCD screen. It's a fantastic monitor. Buy NEC, folks—they're damned nice.
Edit: I shouldn't post before 9am, ever. I can't believe I just wrote about synchronized posting.
Then there are all the things we each say you can post about it which never get posted at all.
All-in-all though, it works quite well.
At least you coordinated beforehand so that you didn't both post about synchronized posting.