Based on Colleen's insight, it seems that the operational consideration for you is whether or not getting an MBA on top of your JD is worth the additional $81,000 (=3* $27,000) or so.
At the 2011-2012 rate, you could expect tuition of at least $58,250 per year. For two years, this would amount to $116,500 (a conservative estimate, given tuition can rise slightly year over year). You would essentially be saving (on tuition and tuition-related fees alone) approximately $35,500 (=$116,500 - $81,000). This does not include other savings (like your time) and other opportunity costs.