One of our admins, Jarek, had scripting experience. He made a server that is hosted on Exosanty's dedicated server. He released it in early January 2011. It is a war server with rotating maps. The server began with barely 5-6 maps for one gamemode, today it has 3 gamemodes and more than 100 maps. Most of these maps are made by Players (90% of the maps). The server features one of widest weaponries ever seen on SA-MP (mines, dynamite, airstrikes, dispenser packs, poison pills, REALISTIC grenade launcher, static miniguns, SAMs, launches with torpedoes, bomber planes, banditos with M4s, etc...). Now more than 1.5 years have passed since the server was released. After some time, the server started loosing its players. soon there was a fight between Jarek and Exosanty. Later, Battlefield was closed. Few months afterwards, Battlefield came up again but not in COD5.

EgzoCanty and JERK conflict

when the egzo nation attacked, everything changed.

(Full development logs here)

v0.01 to v0.26 (November-December 2010): Birth of the server.
Gamemodes: Battlefield. Maps: COD5BF0: Blood in the Lake, COD5BF1: Devil Pine, COD5BF2: Area 51
Classes: Soldier, Sniper, Engineer, Heavy trooper (with a normal RPG), Scout, Assassin (now known as spy), Technician
Special features: mines, dispenser packs, spy disguise kit, teargas effects (a bit bugged at that time)

v1.00 (January 2011): Official release of the server.
Featuring the famous Saboteur, his dynamites and the beginning of people's rage "Ahhhh fucking team mates fuck off from my dynamites!". The server had the old map voting with a selection menu (you had to scroll up/down in a dialog and click on "vote").

v1.01 (January 2011): Birth of Chuck_Norris bot. He couldn't do as many things as he can today.

v1.24 (February 2011): The permanent weapons came out.
They allowed you to have some weapons FOR GOOD if you won its killstreak enough times. For example, if you won 75 times a deagle for doing 4 silenced 9mm streak (in the whole existence of your game account), you would ALWAYS spawned with a desert eagle instead of a silenced 9mm. Similar things for Spas instead of Shotgun, Sniper instead of Country Rifle. Later came permanent headshots and /kks. /kks allowed you to switch between katana and knife at wish.
The map voting also disappeared with this update: maps were always chosen randomly, unless a Lvl4+ admin forced a map.

v1.30 (March 2011): The team bonuses (buyable ones) came out, along with the "Hero" class.

v1.35 (April 2011): The famous version of BF, where we had to chose both the team and class at the same time.
This was an attempt to find a workaround due to the worst bug that the server has known: the famous "class selection bug", which took more than 30-40 versions before being fixed for good. This selection screen was also an EPIC FAIL: everyone complained about it, and the dual selection (the one currently used today) came back with v1.36.

v1.60 (May 2011): Chuck_Norris team bonus. <3
Chuck also became a REAL bot: before v1.60 chuck was only automatic messages and moderation tools. With v1.60, Chuck became a real bot that took 1 player slot and spawned in the admin area.
It's also the beginning of Chuck's chat reaction (and insults).

v1.80 (June 2011): MAJOR turn in the history of COD5 Battlefield:
1) Armed vehicles
2) Disappearing of the permanent weapons
The first armed vehicles came out! Flatbed, Yosemite (it had 2 heavy rockets on the sides, now replaced with the Dune), Rustler bombs, Launch rockets (it couldn't shoot behind at that time). In v1.81 we also had the very first vehicle equipped with dual M4s on the hood: the Patriot. Due to the big amount of patriots on most maps, it's later been replaced with the Huntley (which is still in use today).
In the first version of M4/minigun shots, the "yellow lasers" weren't attached to the vehicle, which made it look VERY ugly when we were shooting while driving..
This version also features the DISAPPEARING of the "permanent weapons". Due to most regular players having most of the permanent weapons (it took long to win them, but once we had them it was FOR GOOD), they could spawn, for example, with desert eagle+spaz as engineer, or M4+sniper+headshots as sniper. In a general way, the permanent weapons were considered as overpowered, and as a MAJOR issue that made rookies rage and leave the server. In order not to get the old player too angry due to this removal, they would get, in exchange, weapon kills for the future achievements, which would therefore allow them to achieve these quicker.

v1.88 (July 2011): The achievements came out!

v1.90 (July 2011): The static miniguns came out!
The SAM sites would come quickly after. The field canons and anti air batteries came out many months later. Note that at that time, static miniguns had a 47HP power! But they were shooting twice slower. They didn't have any "heat" bar also, which allowed you to shoot continuously without letting it cool down.

v2.00 (November 2011): The second gamemode came out! Team Death Match! It came with 3 maps.
Along with it, the good old "vote system" came back, in a totally remade version. This vote system is completely different from the one used bu v1.00, as it needs you to type a number to vote, and it displays the number of votes for each choice.

v2.20 (15/02/12): The third gamemode came out! Free For All! It came with 4 maps.

v2.21_R2 (23/03/12): TDM and FFA now support BF's special weapons, which GREATLY improved the fun and the retardedness we could have in these modes.

v2.30 (19/04/12) New gamemode: Carmageddon! Carmageddon depicts a deadly race packed with unexpected surprises. It includes the ability to fire missles, acquire boost pickups and to drop explosive barrels and road spikes to take down your opponents and win the race. As well as intriguing, it is also fun.

Nowadays: Gamemodes: Battlefield, Team Death Match, Free For All and Carmageddon. Maps: more than 100
Classes: a shitload of different classes