The only standardisation that has gone on is that there are two standard sizes.
As you noted 1.75mm and 3mm.
Vik sells both sizes from his website www.diamondage.co.nz
3mm tends to be cheaper per kg because there is less time and effort to make it than 1.75mm filament.
The lower cost means 3mm has a big following among the RepRap community but the printer designs like Up and makerbot use 1.75mm as standard.
I suspect that 1.75 mm filament is better for precision parts but I haven't seen any in depth study to back that up.
Cheers,
Mike Paauwe
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www.makershop.co.nz]
Makershop - Reprap parts, adding new stock almost daily.
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