Today's the day. UFC 168 in Las Vegas is upon us and the main event fight is huge. Chris "The All-American" Weidman tries to defend his improbable Middleweight title belt against perhaps the greatest fighter of all time, Anderson "The Spider" Silva. They first met last July at UFC 162. Silva was supposed to runaway with a victory, but the champ was caught with his hands on his hips. All that clowning around got Silva knocked to the ground with a flurry of punches. The fight ended after Weidman pounced on the former champ and the referee had to stop the match.

The oddsmakers in that fight had Silva as a -260 favorite and Weidman was a distant +200. Silva is still favored tonight, though, but not a large margin. Many commentators and fans thought that Silva gift-wrapped the win for "The All-American." Whether that is the case or not, Silva's undefeated UFC run came to an unceremonious end. On the flip side, Weidman still has a lot to prove. Many think that if Silva focuses on his striking, Weidman's defensive skills will be exposed. Silva is prone to takedowns, though, and his wrestling is not as refined as Weidman's.

The co-main event features champion Ronda Rousey taking on challenger Miesha Tate in the fairly new women's bantamweight division. #3-ranked fighter, Tate looks to pull off a stunning victory over her archrival Rousey. In their first matchup back in 2012, Tate was the Strikeforce champion. The UFC didn't even have a female division. Tate didn't believe Rousey deserved to challenge her as she had only four fights under her belt. She preferred to face an established veteran like Sarah Kaufmann. Experience aside, Rousey destroyed Tate's left arm via an armbar in the first round. Rousey later made quick work of Kauffman using the exact same finishing move.

Tate was initially seen as the bully when Rousey first called out the former champ. She seemed to be dodging a challenger and developed a villainous role. Tate, of course, felt that Rousey was too green. Unlike the other pro fighters in WMMA who fought dive bar type venues for a pittance, Ronda burst onto the scene. That rubbed Tate the wrong way during the lead up to their first fight and it's still a point of contention for her. Tate's boyfriend Bryan Caraway didn't help her image when he went on a Twitter rampage saying how he would knock Rousey's teeth out. But boy, times have changed.

Rousey's image was tarnished after a stint as a coach alongside Tate on The Ultimate Fighter. The champ was seen as petulant and a bit of a bully. Many UFC fans now want to see her get knocked out. Just browse the comments on her Facebook page to see all the hate. Despite her sullied reputation, Ronda is undefeated and largely unchallenged. Tate shouldn't even be in this fight as she lost her last fight to Cat Zingano. However with Zingano, the number one contender, sidelined with an injury, Tate was slotted in as her replacement. Tate says she is coming off her best training camp of her career and clearly looks to be in elite shape, but she has a lot to prove.

You can watch the prelims featuring William Macario vs Bobby Voelker and Robbie Peralta vs Estevan Payan at 7/4PM ET/PT on YouTube. Additionally you can buy the entire night's fights at UFC.TV or on Ustream. The main event takes place at 10 p.m. ET.

Who are you rooting for? Are you a fan of female mixed martial arts? Let us know your picks in the comments section below.