While the plot is cliche, my friends and I appeared at the midnight showing of 17 Again, clad in "I <3 Zac" attire and huge smiles on our faces. We knew that the movie we were going to see was going to cater our superficial desires to watch a gorgeous Zac Efron for 2 hours; however...
Zac's acting was superb! Everyone in the theater (which seemed to be between the ages of 15 and 23) seemed impressed by his ability to portray a 40-yr. old father! We all laughed at the puns that seemed pointed towards Zac's previous roles, such as when Zac says to his preggo girlfriend "We're in this together."
In summary, seeing this movie is a win-win situation: watch Zac's great performance, and also lose 10 pounds from laughing so hard! :)