Via [url=http://blog.counter-strike.net/index.php/2015/05/11988/]the CS:GO blog[/url]:

[quote=Valve][OPERATION BLOODHOUND]
– Launched Operation Bloodhound, available until September 30th, 2015.
– Six community maps available for free to ALL CS:GO PLAYERS on official servers via the Operation Bloodhound map group: Agency, Resort, Zoo, Log, Rails, and Season
– The Operation Bloodhound Access Pass is now available for purchase. It provides:
— The upgradable Operation Bloodhound Challenge Coin, which can be displayed on your profile and in the scoreboard.
— The Operation Bloodhound Journal, complete with Friends Leaderboards to track your Active Duty and Operation Competitive performance.
— Two all-new campaigns, with 62 missions rewarding additional XP throughout the Operation.
— Earned weapon drops will come from the Operation Bloodhound exclusive weapon collections: Cobblestone, Cache, Overpass, and all-new collections Gods and Monsters, The Rising Sun, and Chop Shop.
— Exclusive access to the Falchion Case, containing 16 community-designed weapon finishes and the all-new Falchion Knife.
— Added two new Mission types, Assassination and Guardian Co-op which are playable via campaign missions in the Operation.
[PROFILE RANKS]
– Introducing Profile Ranks, viewable in-game on your CS:GO profile.
– Play on official servers to earn XP and rank up your CS:GO Profile Rank.
— In Competitive Mode, your earned XP is determined by your rounds won.
— In all other modes, your earned XP is determined by your score.
— You can earn additional XP by completing Operation Bloodhound Missions.
– In addition to increasing your CS:GO Profile Rank, your first Rank earned each week will reward you with an earned weapon drop. If you own an Operation Bloodhound Access Pass, your weapon will come from one of the exclusive Operation Bloodhound weapon collections.
[CASUAL]
– Reduced Round timer from 3:00 to 2:15.
– Increased warmup time from 30 to 90 seconds.
– Disabled vote to restart match.
– Vote to change level is disabled after a team has reached match point.
[UI]
– Fixed sometimes (but rarely) seeing health of players on the other team in the mini scoreboard.
– Fixed the freeze panel sometimes getting stuck on and staying on even after the player is alive.
[MISC]
– Added trace-based visibility checks to prevent networking invisible enemy players.
– Updated CSGO engine to the latest Steam API SDK.
– Improved support for integrated web browser MOTD popups.
– Fixed several server-crashing exploits.
– Fixed voice chat echo in lobby.
– Re-enabled a bunch of player model variants including the much missed Balkan “Ido” model, otherwise known as tm_balkan_variantC.
– Added a convar (sv_disable_immunity_alpha) that when set, allows mods to handle their own alpha on players.
– Limited support for FBX in studiomdl.
– Added sv_vote_to_changelevel_before_match_point (default 0, vote is never disallowed). When set to 1, the vote to change level is disabled after a team has reached match point.
[MAPS]
-Cache
–Fixed multiple bomb-stuck spots
–Fixed an issue where saving CTs could be seen on radar from outside spawn
–Fixed an annoying issue where grenades would collide with ground geometry map-wide
–Deleted a problematic glass pane in mid (thanks RoF Anders)
–Ensured tarps on crates are actually spammable
-Season
–Reduced width of Upper B T-side and long A to their CS:Source dimensions
–Fixed every “white on white” corner to improve visibility (Thanks Shahzam)
–Added a railing on catwalk to ensure that T’s don’t rush A site without potential punishment from pit
–Fixed an angle at B lower to ensure that defensive grenades can be bounced off a wall easily and properly, as was the case in CS:Source
–Made squeeky door louder
–Bug fix: fixed metal sounds being made on all surfaces throughout the map.
-Mirage
–Fixed some spots where C4 could get stuck
–Fixed some spots where players could get stuck on walls[/quote]

Rumor has it:

- The price of an Operation pass is [B][U]$5.99 USD[/U][/B]

- ZionTheKing of reddit [url=http://www.reddit.com/r/GlobalOffensive/comments/37ebes/major_counterstrike_global_offensive_update_for/crlybzs]tore down a whole bunch of aspects of the update[/url], also taking the liberty to link to [B]an image of the Falchion Knife and new knife sounds too[/B]

- Items and item images:

- CS:GO Stash has the new stuff listed, some images will be coming soon but here they are:

- [url=http://csgostash.com/case/50/Falchion-Case]Falchion Case[/url]
- [url=http://csgostash.com/collection/The+Gods+and+Monsters+Collection]The Gods and Monsters Collection[/url]
- [url=http://csgostash.com/collection/The+Chop+Shop+Collection]The Chop Shop Collection[/url]
- and last but not least, [url=http://csgostash.com/collection/The+Rising+Sun+Collection]The Rising Sun Collection[/url]

- Workshop links for the new weapon skins [url=http://www.reddit.com/r/GlobalOffensiveTrade/comments/37ebxa/psa_new_skinz/]can be found on /r/GlobalOffensiveTrade through a compilation post by stokkebye of reddit[/url]

- Item schema update: [url]https://github.com/SteamDatabase/SteamTracking/commit/977b6320b6c2044f457c77eebbf725fb8816330e[/url]

- GC protobufs (for developers wanting to interact with the GC either directly, through the use of SteamKit, or similar): [url]https://github.com/SteamDatabase/GameTracking/commit/e1075ddade230523aea1fb44eafc104ec0b7dbe0[/url]

- Strings (bring your own differ...because GitHub): [url]https://github.com/SteamDatabase/GameTracking/commit/477438f67ba2db076858b530f8c7148d954a7af2[/url]

- Size is [B]close to 500 MB[/B] - data capped users should be alert