I voted electronically!

So I went and voted in the primary election this morning. I voted at Woods Cross Elementary School. Here's how the process went.
I walked up to the table and stated my name. The poll worker said "You are registered as a Republican in Precinct 5." She then handed me a yellow piece of paper. (I'm still not sure what that piece of paper was for. I returned it when I returned my voting card.) Another poll worker at the table picked up a plastic, ATM style card and programmed it using a handheld device that looked similar to a calculator. He then handed me the card and directed me to the voting machine.
At the machine, I put in the card, and it pulled up the instructions for voting. After briefly reading the instructions, I proceeded to vote. Just for kicks, I even touched the back button and changed one of my previously entered votes. After voting, I looked at the printout and made sure it matched my choices. Not such a hard thing to do.
Here are some questions that I had after voting that really make me wonder if this is any better then a punch card ballot.
1) I didn't notice that the machines were hooked to any kind of battery backup. What if there were a brief or even an extended power outage at the polling location?
2) When I put the card in, I wondered what if somebody somehow made their own "voting cards?" Could they then vote multiple times or vote in different races then their own precinct?
3) What if somebody takes the ATM style card home with them? Could they then get enough information to create their own cards to illegally influence an election?
4) The printout made me a little nervous. Someone could figure out how I voted by monitoring the order in which people voted at the machines. I also didn't look at the printout before I started, but, I bet if the advancement of the "receipt tape" didn't work quite right, I could probably see how the person before me voted.
5) What was that silly yellow piece of paper for?