Dunno if you folks on Newgrounds really care but figured I answer this question. It's... complicated. The simplest answer is that I stopped browsing Tumblr regularly to give myself time for other things (mainly Newgrounds as the xp system gives me incentive to browse here more). Another reason is that I feel like my Original Content doesn't really get much traction on there; which is probably due to how rare I post OC and mostly use my blog for reblogging stuff. There's a third thing too but I'm not really sure how to describe it...
I guess kinda like Deviantart it has gone from a site I used to visit all the time to one i rarely visit at all (though with dA I do still visit on the occasion to favorite art I find). Though just like I said in my post on there, I'd rather have a rotting corpse than delete my account entirely.
I've posted my Backpack Hero art and queued a few posts on there. That's at least something.