Sometimes used when someone feels pressured to agree with others, even if hesitant. I didn't like the idea, but I went along with it due to peer pressure.
Pro Tip 2/3
Reluctant Agreement
Suggests agreement without enthusiasm, perhaps to avoid conflict or out of convenience. He went along with the plan, though he had his doubts.
Pro Tip 3/3
Sarcasm Potential
Can be used sarcastically to imply the opposite, especially when one doesn't really agree. Sure, I'll go along with that absurd plan!