SoC: Broadcom BCM2837
CPU: 4× ARM Cortex-A53, 1.2GHz
GPU: Broadcom VideoCore IV
RAM: 1GB LPDDR2 (900 MHz)
Networking: 10/100 Ethernet, 2.4GHz 802.11n wireless
Bluetooth: Bluetooth 4.1 Classic, Bluetooth Low Energy
GPIO: 40-pin header, populated
Ports: HDMI, 3.5mm analogue audio-video jack, 4× USB 2.0, Ethernet, Camera Serial Interface (CSI), Display Serial Interface (DSI)
No more USB Wifi Adapters. Pi 3 already has one.It is so small,you would not notice it at first site, the Broadcom BCM43438 chip is a 2.4GHz 802.11n wireless LAN card , it has Bluetooth with low energy, and supports Bluetooth 4.1 Classic radio . It is built directly onto the board in order to keep costs down, it was designed to get FM Radio but the receiver is not put in it. Furthermore, it dose not need an externatl Antena.
The main chip is Broadcom BCM2837 system-on-chip (SoC) it has four high-performance ARM Cortex-A53 processing cores that runs at 1.2GHz with 32kB Level 1 and 512kB Level 2 cache memory, a graphics processor, and it is linked to a 1GB LPDDR2 memory module on the back of the board.
The GPIO and USB chip have not had any major changes, they will work just the same.
You can buy it online now theough Here