If you're looking for MILF pornstars, then I agree that
PornstarPlatinum is likely what you want - though I would also suggest checking out
ExtremeBank.
For more web-only featured MILF content programs, you may also be interested in:
LadySonia - busty English MILF with a penchant for handjobs and light domination
CreampieCathy - white wife into interracial gangbangs and creampies
Naughty4Cash - home of Desirae Spencer
ChickPassCash - lots of amateur swinger's
If you are interested in the latter, more can be found on my
MILF sponsors list
It is also worth noting that PornstarPlatinum, ExtremeBank, and ChickPassCash have been rather busy of late adding brand new sites to their lineups.