I post about my fandoms, my interests, my life, and occasionally my kids. I am also simming my husband's novel, which will be out in ebook in 2012, and will post shots from that. Some of the stuff I follow has adult content, so careful checking that stuff out. Also, I am most likely the same age as your parents, but as my own kids aren't quite 3 years old yet, I don't think they are on Tumblr.
Thanks to my Tumblr. friends, I am now on Pottermore. I am HallowElm2097.
I mostly follow Sherlock, Supernatural, and Food Porn, with forays into other areas of art or nerdiness or some combination therof. I generally don't reblog things labeled Reblog This, but it's not because I disagree or don't like it. I just don't do it here, or on twitter or facebook. Not my thing. No offense intended.
I also keep a blog musing on dieting and grief, mostly because I need to talk about them and I love tumblr so much I'm doing it here.