It's still got the 3.5mm for my headphones, with USB-C hopefully daisy chaining non Apple displays will finally become a reality, and thankfully my work has upgraded to using wireless technology for displaying screens in conference rooms (which works from OS X and Windows).
The new context sensitive function bar is going to take some getting used to, but I have been using Caps lock for escape for years now and OS X just got native support for mapping that.
Grabbed a USB-C to lightning cable while I was at it. Now I can just bring a single charger and charge either my Mac or my iPhone or both at the same time. I rarely use USB drives, so unfortunately I'll need a dongle for that, but it's not that big of a deal.
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I am more sad that there was no announcement for the Mac Pro/Mac Mini. Also no Apple display, instead handing that to LG, so it looks like Apple is pulling out of the desktop market (I wonder how long the iMac will last).
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Edit: There is one thing I will miss, and that is MagSafe. It has saved my laptop many a time in it's lifetime. I am hoping Apple builds a USB-C to MagSafe cable that provides the same functionality to save laptops from a tripping hazard.