Finally a new version of Arduino Ide released few days ago. 1.6.0 includes a lot of new features. Here is a not so brief list of them:

• Support for multiple platforms
• Boards are detected and listed on “ports list” menu together with the serial port
• Drivers and IDE are now signed for Windows and MacOSX
• Improved speed of build process
• Autosave when compiling/uploading sketch
• A lot of improvements of the serial monitor (faster, backed by modern JSSC serial library instead of old RXTX)
• Find/replace over multiple tabs
• Improved lots of Arduino API libraries (String, Serial, Print, etc.)
• Tools & toolchains upgrades (avr-gcc, arm-gcc, avrdude, bossac)
• Command line interface
• IDE reports both sketch size and static RAM usage
• Editor shows line numbers
• Scrollable menus when many entries are listed
• Upload via network (Yún)
• HardwareSerial has been improved
• USB has got some stability and performance improvements
• SPI library now supports “transactions” for better interoperability when using multiple SPI devices at the same time
• Better support to 3rd party hardware vendors with configuration files (platform.txt and boards.txt)
• Submenus with board configuration can now be defined
• Fix for upload problems on Leonardo, Micro and Yún.
• Libraries bundled with Arduino have been improved and bugfixed, in particular: Bridge, TFT, Ethernet, Robot_Control, SoftwareSerial, GSM
• A lot of minor bugs of the user interface have been fixed

Download link