2 punks looking for quick cash. Good call on changing your house locks. They probably stole your keys so you couldn't quickly go get help or follow them.
Unfortunately I have experienced your pain, as my wife and I were assaulted and robbed several years ago while on vacation. Along with money and jewelry, they stole our phone, the hotel and rental car keys and left us stranded on a dark lonely road at 1 in the morning. No fun.