Download the new RouterOS 6.11 release over the torrent network: http://www.mikrotik.com/download/routeros-ALL-6.11.torrent
Otherwise please visit http://www.mikrotik.com/download to pick exact version!

6.11 changelog:

*) 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;