Think Tumblr is just for teens? Not anymore (Hi, mom!)

SAN FRANCISCO -- David Karp, founder and chief executive of Tumblr, rang the Nasdaq opening bell on Friday to celebrate his company’s $1.1-billion acquisition by Yahoo.

Marissa Mayer was on hand to take pictures and cheer on the Tumblr team (as captured in this animated GIF on Mayer’s Tumblr).

Turns out the Tumblr team had even more to celebrate.

Ever since the blockbuster Yahoo deal blasted the news across the world that there was this little thing called Tumblr, the social network is averaging 250,000 new blogs and 80 million new posts a day, according to Which-50.

In fact, in the eight weeks since the deal was struck, Tumblr has added 14 million new blogs, up 13%, and its audience has added 4.2 billion new posts, up 8%, Which-50 reports.

PHOTOS: Six things rich tech execs splurge on

And it looks like a lot of that growth is coming from “mumblrs� (moms on Tumblr), a whole new demographic. Which of course means a teen’s dashboard is no longer a safe refuge for NSFW GIFs (the rest of you can now officially start having flashbacks to the painful moment you lost your privacy from parents on Facebook).

“How I Taught My Mom to Love Tumblr� is one of the many blog posts documenting the flood of older folks on Tumblr.

Writes Daily Dot’s Aja Romano:

“When I found out my mom was reading my Tumblr, I had a moment of sheer panic. It was as if I was still a teenager and she had burst into my bedroom unannounced.

“‘How did you know I had a Tumblr?’ I gasped. Visions of NSFW fanart and endless GIFs of porn stars who look like Inception characters went off like land mines in my head.

“You mentioned it once,� she responded casually, as if she hadn’t just joined Facebook last year.

Romano notes that the mother of Cooper Fleishman, an assigning editor at Daily Dot, recently started a Tumblr blog about pies.

But rather than be horrified, she was drawn in.

“It’s called A Life of Pie, and the photos will make you yearn for home,� Romano wrote.

So Romano decided to embrace the invasion of the “mumblrs� with a primer on deciphering Tumblr’s culture and its lingo.

“The stereotype of Tumblr as a place populated primarily by shrieking One Direction tweens doesn’t seem to be accurate in the bigger picture—although One Direction is one of the most talked-about subjects on the site,� she concluded.

It’s a more charitable response to the aging crowd of Yahoos than when the deal was first announced. At the time, Tumblr users reacted with dismay. Many users were not born yet when the online portal was formed in 1994, and they feared it would ruin the online service that speaks to their generation. Said one post: “Go away Yahoo you can’t sit with us.�

And even today, those around for Yahoo’s golden years are not necessarily fans of the Tumblr deal.

Brad Garlinghouse, the former Yahoo exec famous for penning the “Peanut Butter Manifesto,� which warned Yahoo was spreading itself too thin, said he’s not convinced the deal will pay off.

“I’m probably a little more skeptical than many about the Tumblr acquisition,� he told the Wall Street Journal.

ALSO:

Will Yahoo splurge on $1 billion acquisition of Tumblr?

Yahoo seeks turnaround with $1.1 billion deal to buy Tumblr

Yahoo’s challenge to be building Tumblr’s advertising business