What's the input and output specifications of the Samsung Infuse wall charger? I want to know if it matches with the Samsung Strive charger so I don't damage the Infuse (I don't have the charger for the infuse at the moment).
If it's a wall charger with plugs that match your outlets, the input range should be covered.

Normal USB chargers are 5 V at up to 1.8 mA.  The voltage is the main concern -- standard USB ports for PCs only go up to 900 mA, which is why they charge slower.  You can see the USB power specs on Wikipedia: http://en.wikipedia.org/wiki/Usb#Power

(In sum, any USB charger that you can trust to do what it says on its specs should work fine.  A crappy no-name charger might lie, but two Samsung chargers should be 100% interchangeable.)