Retrofitting our house with ethernet cable

I'm starting a project this weekend that will hopefully end with all three floors of our house being wired with Ethernet cable (maybe Cat6 but likely Cat5e - haven't looked into the benefits of Cat 6 over Cat 5e though I'm guessing it's just more throughput).

I retrofitted our old house (which was built in the 1970s) is a surprisingly easy manner. I was proud of myself for discovering a technique (not saying that I invented it, just that I wondered if it was possible and then successfully executed it) that I called "re-wiring".

Rewiring

Basically I located the phone lines in our attic and followed them to where they dropped into the walls. then downstairs in the rooms, I unhooked the phone wire and securely taped a nylon cord to the phone line. Back to the attic. I pulled the phone wire out of the wall into the attic and then had the cord in the wall. From here I attached a second nylon cord AND the phone wire to the first cord that was in the wall. Back downstairs. Now all I had to do was pull the first cord back and I had the phone line back in the wall where I wanted it plus a new cord that I could use to pull my Cat5e cable with. Woooo!

On our newer house (we were not the original family or I'd have had the house wired before the walls went up) I'm not sure if this will work. We'll see.