Someone PLEASE mod this up some more. I screwed around with ftp, Google+, and a few other options, but BT Sync beat everything. I installed it on the PC, installed it on the phone, and in the space of a few hours I had 9GB of pictures and videos copied across Wifi from my phone to the PC. Whenever I add a picture on the phone, it appears on the computer. You choose the type of sync (read-write or read-only) and let it fly.
The Android App defaults to only operate when on Wifi, so data charges stay low (but you can override). There's a nice GUI on the Windows/Mac side, but also configuration files that are pretty well-documented online; you could, for example, share your local Windows profile directory, but choose to exclude the Local Settings directory and any file that begins with a ~. My next step is to work with some friends and family to operate as each others' "Crashplan". You can even share to multiple locations, for redundancy.
They have a pretty thorough FAQ and forum. It also works directly off a LAN, so no data necessarily leaves the house. Closed source, but I suppose you could run a Wireshark if you're suspicious. Everything is transmitted with encryption, but is decrypted at the target. If you don't trust the target machine, I suppose you could store a TrueCrypt drive and just share that.
Last week someone was asking for a good DR solution for their home machine. This works for the phone, too.