BB played back on the bubble

[theTourne]

Hi all,
What would your play be here?
I didn't have a lot on the BB. He'd been pretty quiet for a while. Maybe normal bubble tightness.

Party $10+1, 1 Table

CO (2385)
Button (1660)
Hero (2685)
BB (1270)

Blinds are 150/300

Hero is in SB with A [img]/images/graemlins/club.gif[/img] 6 [img]/images/graemlins/club.gif[/img]
2 folds. <font color="red"> Hero raises to 600. </font> <font color="red"> BB Raises all in to 1270. </font> Hero...?

Is this automatic getting nearly 3-1 versus the small(ish) stack? Is this scary because he's been relatively tight and has enough chips to wait for something decent?

Thanks.