Ronda Rousey is already a media darling who is able to tap markets and audiences in a way that other UFC stars can't. It's been questioned if that would translate into actual PPV buys, especially on a card like UFC 184 that's topped by two women's fights and no one else with real name value.
The preliminary card drew an impressive 1.2 million viewers, and peaked at 1.45 million. That's good for the third highest number on Fox Sports 1, coming behind just UFC 168 which was co-headlined by Rousey, and UFC 183 prelims with Silva and Diaz.
As for the actual PPV estimates, Dave Meltzer says it's trending to be fantastic numbers. It's much bigger than what most expected and what other UFC stars are capable of, and it could actually prove that Rousey is the UFC's biggest draw. From F4WOnline.com (Subscription Required):
While it’s too early to get PPV numbers, early indications based on the DirecTV numbers blew away even the most optimistic expectations. The early numbers were said to be far ahead of any Rousey singularly headlined fight in the past. It’s virtually a lock this will break the all-time record for a show headlined by a woman’s fight that the Rousey vs. Liz Carmouche fight did (450,000 buys), and could double the majority of pre-show estimates.
I was told DirecTV numbers were roughly identical to the 1/31 show and Google searches for the show, which in most cases is an amazingly accurate predictor of PPV numbers, were four percent ahead of Silva vs. Diaz, and 26 percent below Jones vs. Cormier.
While numbers will fall well short of the Jon Jones vs. Daniel Cormier fight, there is no current UFC fighter facing an opponent with the name value of Zingano and with such a weak undercard who would have come anywhere close to her numbers. It is possible this could nearly if not double fights like Cain Velasquez vs. Junior Dos Santos and Jon Jones vs. Alexander Gustafsson.
...All trending numbers available at this point back up this show doing far better than expectations. In the U.S., there were 1 million searches for Rousey on 2/28, five times that of second place Anthony Mason (a former NBA star who passed away).
Also according to Meltzer, the UFC will be in the neighborhood of 2 million buys at the first 3 shows of the year alone. By the way it is looking, by the end of April or May, the UFC would've have matched the PPV numbers of the entire 2014.
Jones vs. Cormier of course is expected to be one of the biggest UFC PPV events in recent history stemming from the infamous brawl and subsequent rivalry. Rousey possibly doubling the number of Velasquez/JDS and Jones/Gustafsson which both did well over 310k PPV buys is a big deal though -- especially when you consider that Zingano doesn't have any name value, and the co-headliner featured a debuting female fighter taking on a 5-5 opponent.
While people say her dominance may turn people off, Rousey just came from a 16-second victory against Alexis Davis and even more people have tuned in since. It was Rousey alone who carried this card too, and if the trends hold true, it not only proves she's a legitimate draw on her own, it could show that she is in fact the biggest star in the UFC roster.
Now imagine how much more she could do with a perfect rivalry, one against let's say Cris Cyborg.