What's new in 4.1:

*) fixed problem - RB750 (clocked at 300MHz) Ethernet did not work;
*) fixed problem - routes on some interfaces (like VLAN) were not activated;
*) ppp, gps, sms, serial terminal - allow use of different channels
    on same port across multiple programs simultaneous
*) dhcp server - added support for dynamic address-list entries;
*) hotspot - added support for dynamic address-list entries;
*) hotspot - fixed redirect after login in case if client gets new IP address
   (problem introduced in 3.28);

What's new in 4.0:

*) IT87XX hardware monitoring sensor support;
*) kvm allows to choose emulated nic model;
*) hotspot - fixed redirect after login in case if client gets new IP address
   (problem introduced in 3.28);
*) hotspot - fixed redirect after login in case if client gets new IP address;
*) console - commands like 'monitor', 'torch' and others that periodically
    refresh information sometimes failed to work when started from
    the scheduler;
*) console - scheduled scripts no longer require 'test' policy to run;
*) console - fix issues with scripts that contain lines with trailing spaces;
*) console - add back compatibility with old scripts that use space instead
    of '=' to separate argument name and value;
*) console - following fixes:
    - accept item numbers when prompted by command to specify item;
    - argument names without '=' were matched even when expecting unnamed
        value; this broke code such as:
           :foreach i in=1,2,3 do {}
       here 'i' was matched as argument name "in";
    - 'tab' key did not automatically append '=' after complete argument
        names;    

What's new in 4.0rc1:

*) console - removed support for Lua (will be reintroduced later);
*) incorporated all the bug fixes since v3.30;
*) port remote-access - added 'log-file' property. If value is a non-empty
    string, then all data that is read from the port is appended to a file
    with that name, regardless of the active remote connection;
*) console - removed '/user' from the output of top level '/export' command,
    still can be exported by '/user export';

What's new in 4.0beta4:

*) routing - changed BGP network and default-originate behavior;
*) web proxy - allow to edit error page;
*) console - terminal window size change now does not trigger full terminal
   reset;
*) mesh protocol - improved loop prevention (becomes incompatible with earlier versions);

*) incorporated all the bug fixes since v3.27;

What's new in 4.0beta3:

*) added support for 802.11n atheros based wireless cards;
*) added ability to run other OSs in MetaROUTERs;
*) console: Lua scripting language. http://wiki.mikrotik.com/wiki/Lua
*) console: added nstreme-dual OIDs;
*) incorporated all the bug fixes since v3.23;

What's new in 4.0beta2:

*) console: added 'without-paging' argument to 'monitor' commands;
*) console: now 'without-paging' and 'interval' arguments in of 'print'
    commands work together. Printing can be stopped by pressing 'q' or
    ctrl-c, any other key triggers printing;
*) incorporated all the bug fixes since v3.22;
*) fixed TFTP server logging;
*) fixed problem - "/system upgrade" did not show proper package
   architecture and was unable to fetch new packages;

What's new in 4.0beta1:

*) added support for MetaROUTERs;
*) all test packages are regular ones;
*) console - can mix named and unnamed arguments, can use names for unnamed
     argument values. For example all of the following commands are
     accepted now:
       /ping 10.11.12.13 count=4
       /ping address=10.11.12.13 count=4
       /ping count=4 10.11.12.13