v1.0.1.1 of the InfusionSoftDotNet library has been released to support functions and changes related to the Spring 2012 release of InfusionSoft API as well as the latest CookComputing dll (v2.5.0) to handle the XMLRPC communications.
You can download the source code, pre-compiled binaries and or the History.txt file of all changes from http://infusionsoftdotnet.codeplex.com.