I don't believe launches from the Cape have enough fuel to boost back to Boca Chica though, do they?

All that automation you're talking about is at least a decade out.

The most important aspect of the new launch site is that it is simply another site they can launch from. SpaceX has the rockets, they just need a couple weeks between launches at the moment to get the launch pad squared away and prepped for the next launch. By adding a second site[1], they have double their throughput.

[1] Technically it's the third site, but Vandy is limited in what it can launch, as you can only launch into very high inclination orbits from there.

That's all speculation on the part of the reporter, and a lot of it is oddly ungrounded. SpaceX has already built its own spacecraft prep facilities and launch pads at its two existing sites (Canaveral and Vandenberg), which already are largely automated (you don't want humans anywhere near a fueled rocket!) So it's not like they needed their own site for any of that.

The one part of that speculation that is sourced -- different range safety systems once the rocket is in flight -- does deal with facilities that SpaceX shares with the Air Force and other launch systems (ULA Atlas launches at both sites, at least). But handling of the rockets on the ground is already completely under SpaceX control, and done entirely with their own purpose-built equipment.

The location near Brownsville is amazingly similar to Canaveral. Tidal flats, ocean to the east, barrier island, similar latitude, hurricanes.

They are almost as far south as they can be and still be in the United States, which is where the company is based.

As rkuykendall-com mentioned, its as far south in the US as you can get without overflying other land, and they've gotta stay in the US to prevent ITAR violations.

[+] http://en.wikipedia.org/wiki/International_Traffic_in_Arms_R...

They don't share the pad. They share the range (which consists of multiple pads and various support services (radar, etc)).