The Tax Foundation - State and Local Tax Burdens Compared to Other U.S. States, 1970-2007
Vermont is #1 at an average rate of 14%(highest burden in US in 2007).
Massachusetts is #28 at an average rate of 10.6% (in the middle, despite our nickname)
New Hampshire is #49 (only Alaskans pay less) at an average rate of 8.0%
This only applies if you live and work in those states--you still have to pay MA state taxes if you work in MA but live in NH. Also, the NH property tax burdens vary a lot by municipality. If you want good schools, property taxes will be higher.
When you factor in the federal tax burden, MA climbs a lot because of our progressive federal tax structure and the relatively high cost of living here.