If this is true, regardless of how good the attraction will be, this seems to be Universal's ballsiest move to date. SLoP debuts mere weeks after "Finding Dory" does, and it's not a prior existing franchise, so this is not a "safe bet". It's not, simply because we have nothing to go on besides, "Well kids find cats and dogs to be cute and the teaser had a good reception on YouTube."
It's not a 3D film, it's not a show. We're talking about a full-scale, trackless dark ride with audio-animatronics supposedly being thumbsed up that's based on a movie which won't be released for another eight months.
After spending time debating on twitter and reading the "in the know" from various trustworthy insiders (many of whom are posting in this thread currently), I will say there's one thing people can agree on if this rumor comes to be: it is, without a doubt, a 100% anti-Disney move. Not that it's trying to compete with Disney necessarily, but in that this is something Disney would never, ever do nowadays.
This would be Universal betting money on an untested property for an lavish E-Ticket attraction (if the rumors are accurate), that even if it flops they will just have to own it and make it good enough to stand by itself. And it'll debut within two years after the movie comes out. And its not like the theme parks don't have new attractions coming in, either.
I imagine within the halls of WDI exist numerous concept art drawings of potential attractions based on various Disney properties that will never see the light of day because they simply spent too much time trying to dart through red tape for it, and then gave up because it was already eons since the movie debuted.
And here we have Universal about to slam down a ton of dough for a property that has yet to come into being for the most part (which feels like an extreme overcorrection re: Minion Mayhem), they aren't just confident: they're dowright audacious. If SLoP turns out to be Despicable Me huge, then wow. Bravo, Universal.
If it's a flop... well, let's just say that there's incentive on going full throttle. Nobody blinks their eye at Splash Mountain despite Disney trying to deny existence of Song of the South everywhere else. It'll just have to live out its life as a great theme park attraction despite being based on a mediocre movie. Works for WaterWorld...