Why are people confused?
First iteration of the expansion (patch 4.1)
For Justice points and doing heroics you will buy and get from bosses iLevel 346 blues only (no epic gear).
For Valor points and from the three raids on release you will purchase Tier 11 (with tokens that drop in said raids) and other iLevel 359 epics.
You cannot get epic level gear unless you raid (so for casual players the first patch will be quite sad in that respect).
Patch 4.2
Tier 11 will still require the tokens that drop in the first tier of raids but equivalent epics will cost Justice Points. This means that in the next major patch after release, iLevel 359 gear will become available to people who run heroics and aren't able to raid. Tier 12 will cost Valor points and armor tokens and be something like iLevel 374 epics, and equivalent iLevel epics will cost just Valor points. The three raids that get released with patch 4.1 will then award Justice points rather than valor points.
What this means
When the expansion is released, non-raiders will not have any epic gear. When patch 4.2 hits, many months into the expansion, the playing field is not levelled, as the difference between T11 ranked gear and T12 ranked gear will be rather big. Remember that
they are itemising with T13 in mind, and have worked backwards from there. This means that come 4.2, the lower level of epic gear which becomes available to non-raiders will be good enough to step up into the current tier of raiding but the gear available from doing those raids will be far superior.
It would also be nice to have epic gear drop from the end bosses in heroics, a la TBC - but that won't be, it seems, until 4.2.
So raiders, rejoice, and naysayers, go sit in a corner. So-called "casuals" are not going to steal your epeen-ranked gear.