[Faceman]

seems to me that Bards with higher spell levels in ToB is okay/intended
recently got to Saradush and aquired the Bronze Ioun Stone which gives one extra lvl7 spell and is usable by Mages and Bards. If Bards could not go past lvl 6 this would be senseless as you can't get the extra spells if you don't have a slot already. So I gues it's either plain ToB or was at least intended to be.