Marshall Breeding announced the results of his 2010 ILS Survey and two of the big winners in this year's report are Koha and Evergreen. And, interestingly, the big loser was none other than SirsiDynix.
According the Breeding's data, 150 libraries migrated to Evergreen (I say migrated but his stats often reflect a "contract" not necessarily a migration) and 133 migrated to Koha. In contrast, only 53 libraries migrated to a SirsiDynix product, 48 to Agent Verso, and 28 to Millennium.
Of the 150 libraries migrating to Evergreen, 89 of them came from a SirsiDynix product.
To put it all in even more stark contrast, note that 50 libraries migrated to Koha with ByWater Solutions (versus the other 83 or migrated to Koha with another service provider or did it on their own). That's almost twice as many new customers as Millennium gained in 2010 and only 2 fewer than Sirsi/Dynix.