In his post, The Death of System.DateTime?  Omer van Kloeten evaluates the use of the System.DateTimeOffset object in place of System.DateTime to improve handling of Time Zone sensitive times.

When representing a date/time, especially in an internationally-faced system, you have to include a time-zone. DateTime did a very poor job handling time-zones, like being insensitive to changes. DateTimeOffset is the exact same thing as DateTime, only it takes heed of time-zones. For instance, comparing two DateTimeOffsets with the same UTC time in different time-zones will result in equality.

Moreover, DateTime also had only three modes: Local, UTC and Unspecified, whereas DateTimeOffset has an Offset property, allowing you to create dates in any time-zone you like.

I have not yet experimented with the System.DateTimeOffset type but what Omer says makes a lot of sense to me.  Has anyone else played with this object?