If you are already running a RouterOS 6 install, Simply click “Check for updates” in QuickSet, Webfig or Winbox packages menu.
Quote: What's new in 6.11 (2014-Mar-20 09:16):
*) ipsec - fix aes-cbc hardware acceleration on CCR with key sizes 192 and 256; *) wireless - add auto frequency feature; *) ovpn - fixed TLS renegotiation; *) ovpn - make bridge mode work with big packets (do not leave extraneous padding); *) ovpn - fixed require-client-certifcate; *) ppp - revert RADIUS NAS-Port behaviour, report tunnel interface id; *) ppp - mppe encryption together with mrru locked the router; *) dhcp - added support for DHCP option 138 - list of CAPWAP IPv4 servers; *) quickset - added Guest Network setup to Home AP mode; *) console - no longer required to supply value of '/routing bgp instance vrf' property 'instance' for 'add' command; *) ethernet - added option to enable rx/tx flow control (will be disabled by default); *) ethernet - added ability to specify advertised modes for copper ports; *) fixed 100% cpu usage on CCRs; *) ssl - not finding CRL in local store for any certificate in trust chain will cause connection to fail; *) lte - support for Huawei ME609 and ME909u-521;