Weapon customization to be part of Battlefield 3.
According to the Official BF3 Blog, Battlefield 3 will come with about 50 different types of weapons for you to choose, so that's what we call giving something for every taste :). Basically the weapons now will be customizable on three ways, because each weapon will have three accessory slots, givin you options to adapt your weapon to diferent situations as required. The more time you play with a certain weapon will give you access to unlock more options to customize that weapon; this will result in playing or adapting the game the way you play.
From BF3 Blog.
A rifle in Battlefield 3 can be customized for wildly different combat roles. The carbine directly below has been equipped with a heavy barrel, bipod, and a 4X magnification combat scope. This would be ideal for a soldier who wants to engage targets at medium to long range and use suppressive fire to support his team mates

In the picture above, the same carbine has instead been equipped with a suppressor, foregrip, and quick acquisition holographic scope. This setup would be well suited for Close Quarters Battle, especially indoors where stealth can be a vital factor. The unlockable weapon accessories include an assortment of optics, suppressors, bipods, barrels, underslung grenade launchers, underslung shotguns, foregrips, flashlights, laser sights, and more.
While the class and model of your weapon will determine a number of basic values (like muzzle speed, energy, and fire rate), you can always modify it to tweak it towards anything from long range to close quarters combat. So, are you a long range sniper or a close quarters combat type of player? The neat thing is, in Battlefield 3, you can easily switch between both. With our powerful weapon customization features, there are no limits to the types of gameplay we support.
BF3 everyday seems to be better and appeal more than any other game of the series.