There is still some hope, but it is looking pretty grim.
1. GIMP does not support the 5700i because it does not use Postscript. They also stated they would not write a driver cause it would take too much time.
2. Last Saturday the French site for Epson posted a LaserWriter driver for the 5800 which is a postscript printer. The good thing is that this driver has the Epson utilities in it, so theoritically all that is left to do is the actual driver for the 5700i.
3. I read on another board, that Epson Support had told one person that they would be coming out with a driver in September, needless to say it is now September.
The Omni printer system for Linux does support this printer and maybe even the full blown CUPS also probably comes with a driver, so if Epson can just take some time and port the driver over, it should be a lot closer than if they were to start with nothing.