So I've been interested in purchasing Rocksmith, but I keep hearing that the guitar bundled with it is rather terrible. That's OK, I have a decent bass that I'd actually prefer to play songs with and learn on, but I'm failing to get consistent reports on whether or not you can hook up a bass guitar with the main game. Can anyone confirm or deny if hooking up a bass with the game's included cord would work or not?

I don't think bass is supported, only guitar and vocals (kinda).

According to the bass content FAQ on rocksmith.ubi.com:

I already own Rocksmith™. How can I get the new bass content?
Bass content will be made available as DLC on September 4, 2012.

I don’t own Rocksmith yet… How do I get the new bass content?
You have options! If you buy a copy of the game now for your favorite console, you will be able to purchase the expansion for bass on September 4. There is also an updated retail version coming October 16 which will feature bass content on the disc, and for the first time ever, on PC!

Which songs will I be able to play using a bass?
You will be able to play bass for the 53 songs on the disc that feature Bass mode. Bass arrangements will also be added for all those supported previously released as DLC.

Will I need to repurchase past DLC to play them with bass?
No! The new bass content will add arrangements for all previously purchased DLC.

@desoda: Dang that sounds pretty sweet :).

Jeeze, still waiting till September? I know they talked about it around E3, so I was kinda expecting a mid-summer drop. I am into bass DLC.

In case anyone missed it, they're now releasing this this month:

Rocksmith ‏@Rocksmithgame

Unfortunately the Bass DLC isn't coming out Sept 4 anymore ... because it's coming out 3 weeks early on AUGUST 14th!! http://ow.ly/i/OOb4

:)

@riffingt0n: fucking excited about this, if only to play dat bassline from that Kings Of Leon song. Y'know, where it all goes "boop bop badoodooboop" or something. BUT, it's also, like, 30 bucks, which, hey, considering it's such a big update, of course it would be.

I have the bass DLC and it's worth every penny. Every song you already own gets a bass line, there are new challenges, it supports emulated bass so you can get started with even a normal guitar, and it tracks the progress separately from guitar. They nailed it, it's just wonderful.

And I'm now going out to buy a bass.

Game is out on 28th September in Europe, looks like it'll feature the new Bass mode from launch, on disc.