I plan on getting a Bionic upon release. Here is a comparison on how I choose to buy a new VZW phone (in person). No specific order, just the pros and cons on what I have found to be the case.
Best Buy
Pros : Rebate given up front (no need to mail in, taken at register), no restocking fee upon return/exchange for different phone.
Cons : Based on this thread, not able to do early upgrades for 1 yr contract. Also, don't get their "Black Tie" warranty (I think that is what it is called). It doesn't support physical damage. Get the Verizon insurance instead.
Verizon PLUS corporate stores (if you are lucky enough to have one around as I do)
Pros : Rebate given up front (same as BB). Friendly and knowledgeable staff willing to discuss rooting, etc (at least at my store).
Cons : Restocking fee for returned phones. No other cons, but unsure if they can give a 1 year contract on an early upgrade. I will go there soon and ask and report back.
Verizon Wireless Corporate stores
Pros : None (IMO).
Cons : Very busy, long wait time, restocking fee, mail in rebates, I teach staff about features of phones, etc, etc.
Sadly, I have never purchased online, but perhaps someone who has can list pros and cons from that route.