Black Eyed Peas have a tough act to follow. Not their set at the Grammys, or on New Year's Eve, or the MTV Video Music Awards, or the Oprah season kickoff, or the American Music Awards ... did I forget anything? No, in Pittsburgh, they have to follow their NFL Kickoff Concert in September when they played that exuberant sundown set in front of the Point Park fountain to an excited, towel-waving mob of Steelers fans.

How can the Peas top that when they roll into the Mellon Arena tonight on the The E.N.D. World tour?

"First of all," says Taboo, "we didn't have our setting. Now we have the big production -- lighting, screens, wardrobe changes. There's so much that's been added to our show, bells and whistles. Before it was just our raw energy. We relied on us jumping around and having a good time. Now it's us jumping around times 10 because we have a visual to go behind our energy."

It's been an impressive journey through "The E.N.D." starting one year ago when the Peas went to radio with the bombastic single, "Boom Boom Pow." It went to No. 1 and stayed there for 12 weeks, replaced only by the celebratory "I Gotta Feeling" for 14 weeks, earning them a record for most consecutive weeks at No. 1. After the fourth single, "Meet Me Halfway," peaked at No. 7, they climbed to the top again with "Imma Be." Meanwhile, the album debuted at No. 1 and went on to earn six Grammy nominations, winning three of them.

All in all, not bad for an effort they thought of as an experiment and a departure into electropop, using heavily synthesized beats and vocal touches. Initially, Taboo wasn't even sold on frontman/producer will.i.am's vision.

"For me it took a minute to see where Will's mind was going with the whole direction of the album, because I had never really been familiar with electro music. But he kind of won me over because he compared it to the hip-hop era of the late '80s/early '90s. When he put it like that and used the metaphor of hip-hop being tied to it, it kind of won me over and I saw his vision and understood it."

Lyrically, it's a pure party vibe, more style over substance and a long way from the conscious hip-hop of a song like "Where is the Love?," which still finds a spot in their live set, or "Say Goodbye," from the first album.

"It's all about evolution and for us, we try to think outside the box and not try to duplicate what we've done in the past," Taboo says. "It's more about evolving as a group, evolving as songwriters. I may not have as many words or lyrics as I used to have, but the lyrics that we do have now, it's very catchy and we try to minimize, because it's hard to rap over electrobeats saying too many words. If you do, it's kind of 'elbowy,' that's a term we use, which means it's not a cool style of rapping. But we're learning how to incorporate our style with electro-style beats."

The Peas' takeover of the pop market has been steady since Fergie joined the group and upped their sex appeal on the third album, "Elephunk," which went to No. 14 in 2001. "Monkey Business," with equally loved and maligned "My Humps," peaked at No. 5 in 2005 and spawned five singles, none of which went to No. 1. Taboo says he didn't know what to expect with "The E.N.D."

"We never imagined it would be this successful commercially. We just went in there and made an album we could perform on stage and that we liked. We weren't thinking anything about critics or anything else. We said to ourselves if the fans can't evolve with us, then it wasn't meant for them. But we knew we would connect with other fans. We didn't expect 'Boom Boom Pow' to come out the box and be so successful."

The Peas' success has spread across the world, with a few exceptions, like the Middle East, Taboo says. He offers that the most interesting international gig they've played was in apl.de.ap's homeland, the Philippines.

"We had the president of the country and the army sitting in the front row when we played. Apl's affiliation of giving back to the homeland was received very well by the president. It was kind of strange, but it was exciting because we're going to a Third World country and my best friend is received like a prodigal son. When we walked into the hotel they had the story of his life on television. Apl's very humble, but he's the biggest star in the Philippines, him and Manny Pacquiao."

Having pushed "The E.N.D." for a year, with touring, making videos and playing every conceivable prime-time spectacle, how much do the Peas have left in the tank?

"We've had a lot of time to rest and be home with our families and get that unconditional love, now we're ready to go," Taboo says. "That's important to all of us. Fergie's married. I'm married. A lot of the band members have families as well. We're excited to get on the road and work and give people the Black Eyed Peas experience."

Critics Andrew Druckenbrod and Scott Mervis talk about music on "The Beat," available exclusively at PG+, a members-only web site of the Pittsburgh Post-Gazette. Our introduction to PG+ gives you all the details.