You get scaled up, but it is broken. For example, a level 85 is going to wreck a level 89 because of the way the scaling over compensates. Look at people's health next time you are in a BG and you will see.
Really? I thought it was just level that was scaled, because I know for a fact I only have less health than other players of my class because of gear discrepancies. If we had the same gear while one was 85 and one was 89, we'd both be scaled up to 89 and have exactly the same statistics.
Not Sure if I can post links or not
If you are really interested in gear scaling do a Google search for "Analysis of the Post-Hotfix 5.2 Battleground Scaling Changes" should take you to a really long winded blog by Cynwise. There are couple of articles about gear scaling, I stumbled across them when trying to figure out what level would be best to XP lock a twink in the 20 - 24 Bracket.