Let's do the best news first:

Rose is coming back! The best sounding and feeling handcannon currently in Destiny will be relevant again. It's getting random rolls. The first drop will be the original roll and will come from a quest to open the new competitive playlist. Future drops will come from a weekly challenge in said mode (one per character). I'm excited, I love that gun!

Okay, now for the meat of the update involving Crucible. I'm just going run through really quick, but I advise reading the update.

The first change is the Crucible playlists themselves. Clash and Control are being put into the new Quickplay node. Seems to make sense--having both as separate modes is probably a big population split, so just having the default Crucible mode be both of them in a single playlist is probably smart.

The Rotator Playlist will still exist, but Rumble is no longer a separate playlist and is now one of the weekly modes.

Crucible Labs will be 3v3 Rift on asymmetric maps and will give +25% Crucible XP.

Iron Banner will now replace Quickplay during the week it is active. I like this change. I think most people probably went into IB when it was active anyway, but having it takeover the Crucible when it's active seems fine.

Quickplay and IB will use loose SBMM. Trials still using its current matchmaking system. They're also testing Fireteam Based Matchmaking in Quickplay next season. Should take fireteam size and skill into account when matchmaking. Once they have it figured out it should make the Freelance mode in Trials irrelevant.

And now for the big change:

Competitive Division is the new competitive playlist. It is 3v3 and will have Survival, Rift, and Showdown in the playlist. "These modes showcase a variety of playstyles designed to show how good you really are."

It is a ladder based mode with seven divisions, each with three subdivisions.

• Copper
  
• Bronze
  
• Silver
  
• Gold
  
• Platinum
  
• Adept
  
• Ascendant

There is an intro quest (which awards you Rose upon completion!). Each season you will have to play seven games as placement matches which will place you in an appropriate division tier to start your climb.

Once you reach Gold, your rank will decay if you don't play enough. Once you are up for promotion to the next division, you will have to play a three game series in which you must win 2/3 games to promote. If you are going to be demoted a division, you will do the same thing and winning will allow you to stay in your current division.

There are no extra rewards to grind for (they don't want a repeat of the only pinnacle weapons). Each division will increase your XP gains for all of Crucible (capping at 1.5x for Ascendant) so that you will earn general Crucible rank up rewards faster.

As the Glory playlist no longer exists, the MIDA catalyst will now have a rare chance to drop from any Crucible win.

Iron Banner is changing again with IB: Fortress. It's zone control, but Caiatl gets involved. A screenshot shows Guardians shoot at Cabal turrets. As Cyber already posted, the old armor set from Taken King is coming back.

Shaxx is getting the engram focusing treatment that we've seen with Saint-14 and Drifter, with an interesting change. You will no longer have to "claim" an engram from Shaxx to pull it into your inventory to focus it.

Shaxx is using a new engram system that lets us use the engram stored directly on the vendor for focusing, rather than needing to pull it into your engram inventory. Making this change is more convenient for you and lets us more easily shift the main cost burden from “lots of Legendary Shards and Glimmer” to “multiple engrams.” While the current costs are similar to Gambit's, expect a larger focusing rebalancing pass (read "lower Glimmer and Legendary Shard costs") with Lightfall, as well as all of the ritual vendors converted over into this new system. A wallet item showing you all of the various engram counts will be available in Season 20.

That sounds great! Need more engrams instead of draining my shards is a good cost for focusing, I think. As it is now, I rarely focus anything. They also say legacy sets will be returning to many vendors for focusing after Lightfall releases.

They're currently working on a brand new map for release next year some time, and will also be adding two maps from earlier in D2's lifespan.

I think that's most of the big news, but again, I advise reading the update for all the details. I think these sound like good changes on paper. Interested to see how it plays out. I do wish there was some rewards tied to the competitive mode, even if just emblems and shaders (not too mention ornaments or glows for armor for higher tiers), but maybe that will come if the mode doesn't just die on the vine.