Recent observations by Bania et al. measure 3 He versus oxygen in Galactic H ii regions, finding that 3 He/H is within a factor of 2 of the solar abundance for ½O=H e À 0:6. These results are consistent with a flat behavior in this metallicity range, tempting one to deduce from these observations a primordial value for the 3 He abundance, which could join D and 7 Li as an indicator of the cosmic baryon density. However, using the same data, we show that it is not possible to obtain a strong constraint on the baryon density range. This is due to (1) the intrinsically weak sensitivity of the primordial 3 He abundance to the baryon density, (2) the limited range in metallicity of the sample, (3) the intrinsic scatter in the data, and (4) our limited understanding of the chemical and stellar evolution of this isotope. Consequently, the 3 He observations correspond to an extended range of baryon-to-photon ratio, ¼ ð2:2 6:5Þ Â 10 À10 , which diminishes the role of 3 He as a precision baryometer. On the other hand, once the baryon-to-photon ratio is determined by the cosmic microwave background, D/H, or 7 Li/H, the primordial value of 3 He/H can be inferred. Henceforth, new observations of Galactic 3 He can in principle greatly improve our understanding of stellar and/or chemical evolution and reconcile the observations of the H ii regions and those of the planetary nebulae.