I'm not sure if this is related to the new SDK release, but the following infragistics controls started appearing when I tried adding columns to my datagridview (the ones that start with Ultra). I don't have an infragistics license, so just wanted to report.
EDIT: I just noticed if I try to add a control it works fine, but if I reset Visual Studio then it complains it cannot find the references.
This seems like some weird bug with Visual Studio.