I remember trying on a pair of the 2001 retros and they fit true.
9 years later, with all my shoes still being a size 11, i decided to go 11
and yes, they are true to size.
Mind you, i have wide feet and order half a size up in air maxes and kobes.
But in general, nike basketball shoes almost always run true.
And foams, once they mold into your foot, do expand a bit (very little, but
take with a grain of salt and a pinch of experimentation).