If you had not guessed it, we use the same format as is used in the Build-Depends field (except for the lack of wildcard support). So you should be familiar with it. Note that the syntax of the overrides should be backwards compatible, so unlike the 2.5.0~rc1 upload, your overrides should still work! A little heads up for people going to DebConf11: We will do a Lintian BoF again this year, yay!
# We like our code without pic on x86, thank you