A blast is just a burst at range.
While a burst is centered on the caster, a blast is centered on whatever target square the caster chooses (based on targeting restrictions).
I, too am concerned.
I was really looking forward to the two Dungeon Bash expansions, Urban and The Wild. I know that they weren't at the forefront of the development stack but it looked promising that work was being completed on them.
Flyspeck23, where have you gone? We miss you.