Do I need a console/serial programming cable?

Yes if you want to flash a new kernel onto the board. We are in the early stages of putting together a 'stable' distribution for Bifferboard, so until then things will be in a state of flux. You will also need the serial cable to see the kernel start-up messages which may indicate why your system is failing to boot.

1MB Flash RAM, that's not very much is it?

If you compare with other commercial embedded devices, no, however Bifferboard is designed to be used with a USB flash drive, or possibly an MMC memory card, which will provide a large amount of storage at very low cost. Consider the flash less of a program storage area, more like a PC BIOS, which is usually only 256KB or so.

I want to build latest sources, how can I do it?

If you want to build latest source, you can get it via svn:

svn co https://bifferboard.svn.sourceforge.net/svnroot/bifferboard

Short changelog is available at http://bifferboard.svn.sourceforge.net/viewvc/bifferboard/?view=log

I have bought board, now what? How can I start using it?

After you get your board, first download latest firmware. Easiest way is to get it in binary form from BifferBoard firmware. When you get it, unpack it and ....