<p>I'm looking to calculate the number of months between 2 date time fields.</p>
<p>Is there a better way than getting the Unix timestamp and then dividing by 2 592 000 (seconds) and rounding up within MySQL?</p>

The
DATEDIFF
function can give you the number of days between two dates.  Which is more accurate, since... how do you define a month?  (28, 29, 30, or 31 days?)