The April 19 Academy of Country Music Awards will go down in history books as the year that (a) Carrie Underwood became the first woman to win entertainer of the year twice, (b) Lady Antebellum ended Rascal Flatts' seven-year run as top vocal group and (c) Brooks & Dunn performed for the last time as a duo at the ACMs.

It might also be remembered as the first "Snakes on a Plane" version of the ACM's annual showcase. The 2006 horror film starring Samuel L. Jackson was a weirdly interactive picture in which producers allowed fans to vote online on some aspects of the plot as well as the songs on the soundtrack.

As a result, it created a huge amount of buzz-and some hiss-among moviegoers. The ACMs, which were initiated as an industry-voted awards show, have experimented with fan voting for some time, including early presentations of the Home Depot Humanitarian Award.

The 2010 show featured more opportunities than ever for fans to shape the performances and the winner's circle:

• Fans selected "My Maria" as Brooks & Dunn's last ACM Awards song.

• They gave Underwood the entertainer trophy.

• They responded to Luke Bryan's video campaign for new artist of the year, selecting him over Joey+Rory and Gloriana, who had won new duo and new group honors in a previous round of voting that was also conducted among fans.

• They were encouraged to vote on what city will receive the Kaboom playground, built with the assistance of the ACM, Home Depot and Humanitarian Award winner Montgomery Gentry.

Kenny Chesney took issue with the fan vote for entertainer the last year that he received the award, noting that it altered the meaning of the honor. The winners' list is now a hodge-podge of trophies, some bestowed by peers, others by fans. The tech-savviness of some of those artists' fan bases may in turn influence their performance at the virtual ballot box.

The ACMs, meanwhile, are serving multiple masters: the industry, the TV networks and the audience the network is attempting to attract. The Country Music Assn. trophies are generally regarded as the ultimate industry stamp of approval, while the CMT Music Video Awards are conducted primarily as a fan-voted endeavor.

That leaves the ACM attempting to carve out a niche somewhere between them.