I notice them everywhere today. I'm usually not organized enough to have something ready, but I'm not sure it would be worth the effort to make a joke. I typically think that if you, like me, are making something sequential, it's probably better to avoid doing things that won't be part of that, or at least won't add to the whole.
I'm sure an April 1st has been on Thursday during the time I've made comics, but not this year obviously. Maybe when it doesn't happen I should reconsider.