One more tip in response to a question from Pizzaman. Since there doesn't seem to be much activity in these forums, I think it makes sense to at least post/discuss these so we have
something to talk about

.
If you have a need to convert integer or string values into Key values (for use with IsKeyPressed), or SpriteState names into the enumerated value of the same name, C# does provide a means to do this. See the code below for an example:
Key k1 = (Key)17;
Key k2 = (Key)Enum.Parse(typeof(Key), "D");
Sprites.Player.State playerState = (Sprites.Player.State)Enum.Parse(typeof(Sprites.Player.State), "Climbing");
For more information, see the MSDN pages about
typeof and
Enum.Parse.