Yes Infamous is better, but Prototype is not a horrible game either. It just frustrates me to lose a post when I have made sure my thoughts were coherent and articulate. However here is the Cliff Notes Version...

1. Powers
InFamous - Electricity fits the story and the power progression makes sense and even powers you recieve in the beginning are useful/necessary throughout the game. *Winner*
Prototype - Mighty Morphin Body is interesting, however the powers require experience points, and are only useful for one specific task. Also the types of powers are more varied, however if only one of those powers kicks ass - who cares about the variety of powers you will never use? *Loser*

2. Travel
InFamous - Cole is pretty much an electric Spiderman, although unless using the railroad tracks or powerlines to speed down it can take some doing getting around the city. However the movements are very fluid and precise, and the superior UI. *Winner*
Prototype - Speed Demon, while the speed boosts and sonic jumps are fun and makes travesering the city quick and easy, there is no precision in his charging through the city. If you are aiming to land on one roof, expect to run right past it, or veer off to the building next door because there is no way to moderate the speed. (You can run up buildings - opposed to InFamous where you climb and shimmy) You are an uncoordinated Bull in a China Shop...*Loser*

3. Side Missions
Infamous - Although most are "Kill this gang of bad guys" at least doing so clears a part of the map, so there is incentive to do the side missions. As well as some variety where you have, rescue missions, stealth missions, etc...
Prototype - Kill and Devour Mr Bad Guy or Race to the Next Checkpoint... That is it. And given my previous description of how hard it is to control Speed Racer - you can imagine how hard it is trying to race and precisely pass through each checkpoint.


I would play Infamous, however if you do not have a PS3 and only have access to an Xbox or PC I can't recall if it is on PC) and enjoy sandbox games Prototype would be a decent distraction...