Yep. Especially with Amazon's "mom club" and subscribe and save programs and free shipping over $25 (or Prime membership).
For example, we use Earth's Best diapers. $45.99 at diapers.com, or approx. $25 at amazon for 120 diapers.
We also use Huggies Overnights for nighttime diapers. At diapers.com = $24.49, and at amazon I will normally pay approx $17 for 64 diapers (paid $12.25 last night because I sed a 20% coupon from Parenting magazine).
Re: better diaper deal: Amazon vs Diapers.com