In reply to afrosam:
There have been lots of forum threads on classic routes on Kaly and routes to do at all grades. Search Forums in the menu should reveal all.
I think an 80m rope is useful for certain routes on Kaly but lots of climbers still get away with a 70m . The only significant advantage of thinner ropes is weight. Thicker ones will probably last longer though.
The current guide is the 2010 edition but it has been reprinted with several grade corrections. Buy it here or there the price is about the same but if you buy it now you will have time to make decisions on routes to do.
Climbkalymnos website has full updates on recent additions and you can get various printed updates cheaply on the island - Try the Glaros bar for extra info when you are there.
The logbook pages on here are also worth scanning for tips and comments on many of the most popular routes.