DeliverIncoming and DeliverPromote Messages

Recently I've worked on a task, when the user click on the "Track in CRM" button in his Outlook, update some field of the recipients of the email, who are a CRM users. Problem I faced I was not sure what message register the plugin on. At the beginning I've tried register plugin on  Create / Update messages. Plugin was successfully fired, but fields To, Cc, Bcc of the Email entity instance were empty and I was not able to iterate through the list of the recipients of the email. Right messages for this purpose are DeliverIncoming / DeliverPromote. DeliverIncoming message is fired when the user clicks on "Track in CRM" button, and when you have registered image, all recipient fields will be populated with actual values in this case.
JFYI: Here is the list of supported messaged for plug ins.

ActivityParty issue

In some my previous post a mentioned issue with iterating though IEnumerable<ActivityParty> collection.

CRM 2011 plugins

Yesterday I tried to write simple plugin against Dynamics CRM 2011. This plugin should update some property of contact in case if some activity is completed. In particular we have to set property new_lastcontacteddate if phone call is completed. In previous CRM version such plugin was arduous since we was able use only DynamicEntity. WSDL generated classes were not suitable in plugins since Microsoft.Crm.Sdk.ICrmService didn't support those generated classes. In order to use strongly typed classes in plugin in CRM 4.0 you could create new CrmService object in the plugin, but it is not good idea