Not that you necessarily need to replace everything, but in mountain biking I saw that SRAM and Shimano (playing catchup) have started releasing their own specific 1x11 groupsets.

SRAM started with their SRAM One which is incredibly expensive but was just the start. These are the ones that are available or officially announced and we're just waiting for availability:

SRAM Gx 1x11 - $564 (midrange)
Shimano XT M8000 1x11 - $424 (midrange)

Sram Nx 1x11 - $310 (lower end)
Shimano SLX 1x11 - (similar price, lower end)

Of course I found this out immediately after...my bike shop ordered a bunch of parts to replace broken parts on a family members bike with 8 speed stuff. :-/