It's gone mad. I saw a rigid Summar go for 1250 GBP yesterday. I know it's rare and all that, but the front element was visibly scratched to oblivion.
Buy Zeiss or CV and wait for prices to come down; it's an M9 driven/production constrained bubble. I can't believe anyone is really buying a two grand lens for a cheap Micro 4/3 digicam.
Ken Rockwell's site (provocative as usual) suggests you should always buy Leica lenses because they are cheap compared to an M9 body. They are not cheap compared to an M3 body, not at the time KR wriote that and certainly not now.
Leica lenses are great but they're not four times better than a Zeiss.