OK so it's not for 2010 - but they might do the same then - have a look at Thomson's The Calypso routes, based out of Thessaloniki. I did Crimean Discoveries B in late September last year and it really exceeded my expections.

I know they are doing Greece/Greek Islands/Turkey this year, so that may continue in to 2010. Perhaps Thomsons call centre might be able to help?

Where have you looked.

try somewhere like
http://www.vacationstogo.com/ticker.cfm
and do a curtom search with a port of choice or a search of area.

Easycruise,

Some others have most of the ports in Greece Turkey
Norwegian Gem
Celebrity Summit
Celebrity Solstice
Splendour of the Seas
Navigator of the Seas
Seabourn Odyssey
Costa Allegra

Depends what you mean by "Greek Islands". Pleanty of cruise companies sail the Aegean. A couple of years back we took the Thomson's Pearls of the Aegean cruise that started in Corfu and stopped at Athens, Turkey and the island of Santorini. They still run this on the Celebration.