Overwatch won't have traditional dedicated servers, but players will be able create private, custom games.
Dedicated servers are a kind of staple for online shooters, allowing players and ISPs alike to purchase servers and customize them to their hearts content. When Blizzard's new TF2-esque shooter Overwatch launches, however, it will be lacking the feature. What it will have is a suite of servers hosted by Blizzard itself, in a similar fashion to Diablo III, meaning that players won't have to deal with the dreaded peer-to-peer server system of *shudder* console shooters.
"Overwatch will run completely on Blizzard servers. With that said, and when we do matchmaking it will be in a Blizzard pool, we are looking at regions and IPs and doing the best to minimise any sort of ping issues," Blizzard's Jeff Kaplan told Kotaku.
He did clarify that the game would certainly have a sort of private custom game option, allowing friends to play together, as well as muck about with custom settings. "We'll allow you to set up some of those things that traditional dedicated servers allow you to do. Basically give you a safe place to go play a match to play with your friends and not go into the big matchmaking pool, we'll have a setup that will allow for that as well," he said.
Kaplan also confirmed that Overwatch, being a Battle.net game, will completely lack any sort of LAN play function.
While not having private dedicated servers, the option to make custom games does sort of make up for it. The only thing that will be lacking is the community - PC shooters like TF2 and CS: GO often build distinct communities within their dedicated server networks, as you'll usually find yourself playing with the same players if you stick to one server.