Just to make it clear: you won't have to wire your house yourself before U-Verse is installed - AT&T tech will do it for you. The most important things to realize is that AT&T tech can use either coaxial cable (adding to existing TV cable in your house), or wire your house with cat5e Ethernet cable. I am just letting you know that it is apparently up to you to ask the tech to use Ethernet cable instead of coax. If you don't ask, the technician is likely to simply add coax cable because it's less work, but if you ask for Ethernet, you should be able to get it. And since (at least in my case) they wire up to 10 locations in your house for free (up to 4 TV sets and 6 computers - they will wire only existing TVs and computers/game consoles, not planned or desired one), you can upgrade your house by getting Ethernet cabling for free when you sign up for AT&T U-Verse.
I asked U-Verse installation tech to use CAT5 Ethernet wiring instead of coax, and he didn't mind. He wired all rooms where I have TVs or computers with Ethernet CAT5e cable, and hooked them up using RG ports and a Netgear Gigabit switch AT&T provided. Needless to say, you can add any number of computers later if you deploy your own switches, preferably Gigabit ones to ensure there is plenty of bandwidth to carry multiple TV streams along with regular network traffic. Wiring up your house for Ethernet is a good freebie from AT&T. Be sure to tell your U-Verse sales person how many rooms you want to wire. Also make it clear to the installer tech which rooms with TVs and computers you want to wire BEFORE he starts. If you change your mind or remember you left out a room with a TV or PC, AT&T will charge you for added wiring.