CiviCRM is a free, libre and open source software constituent relationship management solution. CiviCRM is web-based, internationalized, and designed specifically to meet the needs of advocacy, non-profit and non-governmental groups.
iDeal has nothing to do with Apple but everything with paying securely on the Internet. It is a Dutch solution that worked wonders for increasing the amount of money collected in the Netherlands during the latest WMF funding rally.
As the chapters are becoming increasingly proficient in doing their "thing", a high quality relation management system can make all the difference. As CiviCRM is the tool used by the Wikimedia Foundation, it is almost an obvious choice for the chapters. It would be even more obvious when it moves from the top of Siebrand's list of prospects to the list of projects supported at translatewiki.net..
On the Dutch CiviCRM forum there is a discussion about writing an extension to support iDeal. WE know that iDeal made a big difference in our fund raising. When CiviCRM is the tool used by both the Foundation and chapters, it would be obvious for the Dutch chapter to consider supporting this development.