I've noticed it too. And I was disappointed when Ursula moved her blogging offsite, even though it's mirrored and she still comments.

FWIW I've always been more active in people's comments than on my own LJ. Actually, I first got an account just so I'd have a username in comments rather than being anonymous, and only started posting for myself much later. I got the permaccount so I'd have lots of icons for scans_daily, which kinda backfired when SD got the boot.