Pros :
- A near future without having to manage 4 kind of different USB cables (Mini USB, Micro USB, USB B, USB B 3.0) by having cable be finally symmetrical. USB C on both ends. One cable to rule them all.
- Having a thinner and lighter laptop because USB C all around make a thinner form factor possible.
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For me, the pros far outweights the cons.
Plus, USB C is not like Thunderbolt of Firewire, or even lightning (for the iPhone). It is really the direction the industry is going for lots of very legitimate reasons. Even on my gaming PC with a relatively cheap motherboard I have a USB C port.