Arch Linux and Nvidia Optimus technology

I recently ordered a Lenovo t420 and it is coming in the mail. I opted for the version with the Nvidia NVS 4200M graphics card with Optimus and switching between the Nvidia card and Intel HD Graphics 3000. I've been doing a bit of research and found a lot of older forums threads suggesting things like turning off the Nvidia card in the BIOS. I also found an interesting project called Bumblebee which allows running programs through the Nvidia card. I guess my real question is if anyone has any experience running Optimus on Linux.

TL;DR - Anyone know the current state of Arch / Linux support for Nvidia Optimus in Linux?

EDIT: I'll try to keep a summary of suggested solutions here and a link to a blog post once I get this working on my laptop.

Suggestions:

• Use Bumblebee for running programs through Nvidia card and turning Nvidia card on/off Bumblebee on Archwiki

• Use ACPI acpi_call in AUR