Well I have been playing D3 since day 1 and even before as part of the beta test. So I have been playing D3 for over a year! Barb was one of my favorites in beta, but I started with Wizard upon release, then made a DH after I found out how bad teleport was.
Then I returned to Barb. I missed the 'early' days of inferno. I think I made it to inferno on Barb back when ilvl 63 only dropped in Act3/4. Shortly after, they patched to allow ilvl 63's drop in all Acts, which made things considerably easier.
The Dark Times
The most popular skill pre 1.0.3 was Revenge:Provocation. It was considered mandatory. I did not get to play this much, as I did not clear inferno at this point. Monsters did a lot of damage in Inferno, and getting killed in 3 shots in Act 3 was pretty typical, even with very high defenses. You would mash the revenge key while using Frenzy:Sidearm to kill stuff. If your revenge button did not light up in time, you died!
2H Wrath/quake was the most 'interesting' build and relied on killing elites in one massive burst before you died yourself. All builds relied on WotB:Insanity, Revenge, and rotating defensive cooldowns to try to burst down elites.
The Sprint Era
In this era, WW build was in it's infancy. There were some people experimenting with Sprint, but no one had figured out how to combine it with WW properly. People were figuring out it did the most damage of any fury spender. Most tactics involved something similar to Blizzard/Hydra kiting, except using tornadoes.
2H was still going strong, and some very highly geared 2H barbs were able to farm A3 with some competence. Many SnB barbs were quitting after beating the game out of frustration.
Dawn of WW
Gear had improved enough that WW/Sprint became viable with ~2K LoH in Act 3+. Enough 1H weapons were in circulation that you could create a dual wield set. Sprint had a ridiculous proc coefficient which made LoH incredibly good and perma-wrath was easy mode with 0 ias and 40% cc. 2H weapons were awful compared to dual wield setups, so only a select few persisted with this playstyle.
WW build was Warcry, OP:CA, WW, Sprint, WotB:ToC, Battle Rage:ITF.
Some ran bash instead of OP:CA or Warcry.
Most people were hitting the Ghom wall at this time. It was discovered you could use Overpower:Crushing Advance. The reflected damage proc'd life on hit, making you invincible with ~ 1K LoH. Elites still enraged at this time, but with LoH and WW build, you could power through it.
Another prominent build was 'bulldozer.' For a while, merciless charge would reset based on hits registered with tornadoes, so you could spam this instead of WW with good results.
There were naysayers then as there are now -- "ballerina barbs" were lame...
Age of Experiments
Nerfs to OP:CA proc, and Charge proc off tornadoes, coupled with buffs to all fury spenders (except Sprint) ushered in a new age.
Patch revamped all Barb fury spenders to be roughly equal damage with sprint tornadoes. There were a lot of different builds for a while. The most interesting was the Devil's Anvil HotA build. The proc coefficient was incredibly high on the slowing tremors, so LoH gains were absolutely nuts. You could tank ridiculous damage. The healing was similar to Overpower + LoH, so it was a way to kill any nasty elite combo easily.
At some point, bulldozer was nerfed, so that build died. HotA:Devil's Anvil proc rate was also nerfed, killing that build.
Age of Alkazier
All the experiments have concluded and there is just one effective build: WW. Paragon leveling is what most people are doing now. All fury spenders have been tried, and Rend, Sprint, WW, are determined to be the best. If you don't cram as many of these into your build as possible, along with WotB:ToC and Battle Rage:ITF you are a noob! Devil's anvil showed promise, but it was nerfed to the ground.
WW is king in the MP0 landscape. All other skills do too much damage to be effective. Many are finding they do too much damage to farm effectively and nerf their damage on purpose. Seismic slam and throw barbs are also on the scene in some numbers, but anything works in MP0 with good gear.
Age of WW, HotA and WW hybrids
Bonus CC to HotA based on fury total finally made this skill appealing. So now we have two builds! This is the current age. Sprint proc coefficient is nerfed substantially to kill LoH for WW. It doesn't kill the build though! More gear and nerfs to defensive skills makes more offensive builds possible, so hybrids are born.