They are both so similiar, but yet, different. To me, Lincoln feels kind of like a mix of a "Omaha" and a "Ft. Collins, CO", and has a certain energy, that I don't feel Omaha quite has. Omaha feels more like a mix of a "Lincoln" and a "Kansas City", or something, to me. It all comes down to Lincoln has the "college town" thing goin' on. Omaha has young and fresh qualities, too, with the downtown attractions and music scene, but to me, it also feels more...more...whatever that feeling is you get when you drive by Mutual of Omaha, or, the Woodmen or UP. I feel it feels more established and branded as a center of "big business" on the map & on the nation's conscience, on the river...of family and corporate life and play...of a baseball game on the weekend, or taking the kids to the zoo.
Growing up in Omaha, I really didn't give Lincoln much of a chance, nor really explored it that much. It sat a ways off the interstate, that is why. I had been to the Capitol Building downtown and UNL, and that's mostly it. However, upon exploring it more in recent years, I'm really impressed. It really is a nice, tidy, progressive, energetic, small-to-mid-size American city with a healthy, neat downtown, a nice leafy inner city, and very nice, new suburban areas surrounding the core.
I've always liked Omaha, but I almost equally like Lincoln. In certain ways, I like Omaha better. Yet, in certain ways, I like Lincoln better. I feel like Lincoln is more "cradled in Nebraska" (as a whole more) than Omaha. It is not on the very edge of the state, and with what business goes on there with UNL, the Huskers, and the government, one could argue it has more "center of the state" qualities.
Omaha is 100% Nebraska, it is Husker country, but being on the very edge of the state, and being the biggest city, I've heard it said that the mentality in Omaha is "Us...and the rest of Nebraska." I don't think that is entirely true with everybody, but I understand that thinking, growing up in Omaha and the mentality that can exist in the largest city, in a state that is very rural.
Aaah, good ole' Omaha... Gotta love it. And, Lincoln, too. (Ultimately, I'm proud NE has two great, clean growing cities, soon tied together by a busy 6-lane interstate!)