mini/micro, doesnt matter much when you have a USB cable that has both on the ends...
Amazon.com: Dual Micro USB / Mini USB Splitter Cable. Charge up to Two Micro or Mini USB Devices at Once From a Single USB Port. Ideal for Digital Cameras, Smartphones (BlackBerry, Moto Droid, Palm Pre, etc) and More: Electronics
That with a standard outlet plug usb charger that comes with most smartphones and you are good to go.
Miniusb is good since you can use the cable with literally thousands of other products, then get a micro adapter for the phones.