Here's whatsnew:
* Major source code cleanup
* Completely rewrote memory mapper to support runtime MMCs
* Updated S-DD1 MMC to use new memory mapping interface
* Improved S-DD1 emulation, thanks to information from orwannon
* Added support for SameGame -- load via "Load Special -> Load BS-X Slotted Cart" menu option
* Completely rewrote cartridge loader to support BS-X, BS-X slotted carts and ST carts
* Created custom dialog windows for multicart loading
* Improved generic memory mapper, which eliminates the need for cart.db [Nach]
* Added BS-X slotted cart detection to generic memory mapper [Nach]
* Linux port will now ignore keypresses when window is inactive
* Linux port will use much less CPU power when idle
* Added detailed compilation instructions to Makefile for Linux port
* Added "make install" target and PNG program icon for Linux port
* Switched Windows compiler to MinGW/GCC4
* Windows executable is now packed with UPX to decrease filesize
* Removed .ufo, .gd7 and .078 ROM extensions; added .bs extension
* Added preliminary support for the BS-X base unit, BS-X base cartridge + MMC, and BS-X flash I/O

Get it here:
http://byuu.cinnamonpirate.com/bsnes/

-Trebor