Got the Date and Date/Time new property editors created, fixed up a few date casting issues with data. These editors 'should' be compatible with the previous legacy date/datetime editors, just need to test it.

src/Umbraco.Web/Models/ContentEditing/ContentPropertyDisplay.cs

@@ -22,7 +22,7 @@ namespace Umbraco.Web.Models.ContentEditing
         public string View { get; set; }
 
         [DataMember(Name = "config")]
-        public IDictionary<string, string> Config { get; set; }
+        public IDictionary<string, object> Config { get; set; }
 
         [DataMember(Name = "hideLabel")]
         public bool HideLabel { get; set; }

src/Umbraco.Web/PropertyEditors/DatePropertyEditor.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Collections.Generic;
 using System.Text.RegularExpressions;
 using Newtonsoft.Json.Linq;
@@ -10,13 +11,58 @@ namespace Umbraco.Web.PropertyEditors
     [PropertyEditor(Constants.PropertyEditors.Date, "Date", "datepicker", ValueType = "DATE")]
     public class DatePropertyEditor : PropertyEditor
     {
+        public DatePropertyEditor()
+        {
+            _defaultPreVals = new Dictionary<string, object>
+                {
+                    {"format", "yyyy-MM-dd"},
+                    {"pickTime", false}
+                };
+        }
+
+        private IDictionary<string, object> _defaultPreVals;
+
+        /// <summary>
+        /// Overridden because we ONLY support Date (no time) format and we don't have pre-values in the db.
+        /// </summary>
+        public override IDictionary<string, object> DefaultPreValues
+        {
+            get { return _defaultPreVals; }
+            set { _defaultPreVals = value; }
+        }
+
         protected override ValueEditor CreateValueEditor()
         {
-            var editor = base.CreateValueEditor();
+            var baseEditor = base.CreateValueEditor();
 
-            editor.Validators = new List<ValidatorBase> { new DateTimeValidator() };
+            return new DateValueEditor
+            {
+                View = baseEditor.View
+            };
+        }
+
+        /// <summary>
+        /// CUstom value editor so we can serialize with the correct date format (excluding time)
+        /// and includes the date validator
+        /// </summary>
+        private class DateValueEditor : ValueEditor
+        {
+            public DateValueEditor()
+            {
+                Validators = new List<ValidatorBase> { new DateTimeValidator() };
+            }
+
+            public override string SerializeValue(object dbValue)
+            {
+                var date = dbValue.TryConvertTo<DateTime?>();
+                if (date.Success == false || date.Result == null)
+                {
+                    return string.Empty;
+                }
+                //Dates will be formatted as yyyy-MM-dd
+                return date.Result.Value.ToString("yyyy-MM-dd");                
+            }
 
-            return editor;
         }
     }
 }

src/Umbraco.Web/PropertyEditors/DateTimePropertyEditor.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Collections.Generic;
 using Umbraco.Core;
 using Umbraco.Core.PropertyEditors;
@@ -9,12 +10,18 @@ namespace Umbraco.Web.PropertyEditors
     {
         public DateTimePropertyEditor()
         {
-            _defaultPreVals = new Dictionary<string, string>() ;
+            _defaultPreVals = new Dictionary<string, object>
+                {
+                    {"format", "yyyy-MM-dd HH:mm:ss"}
+                };
         }
 
-        private IDictionary<string, string> _defaultPreVals;
+        private IDictionary<string, object> _defaultPreVals;
 
-        public override IDictionary<string, string> DefaultPreValues
+        /// <summary>
+        /// Overridden because we ONLY support Date + Time format and we don't have pre-values in the db.
+        /// </summary>
+        public override IDictionary<string, object> DefaultPreValues
         {
             get { return _defaultPreVals; }
             set { _defaultPreVals = value; }

src/Umbraco.Web/PropertyEditors/DateTimeValidator.cs

@@ -2,6 +2,7 @@ using System;
 using System.Collections.Generic;
 using System.ComponentModel.DataAnnotations;
 using Umbraco.Core.PropertyEditors;
+using Umbraco.Core;
 
 namespace Umbraco.Web.PropertyEditors
 {
@@ -13,7 +14,7 @@ namespace Umbraco.Web.PropertyEditors
         public override IEnumerable<ValidationResult> Validate(string value, string preValues, PropertyEditor editor)
         {
             DateTime dt;
-            if (DateTime.TryParse(value, out dt) == false)
+            if (value.IsNullOrWhiteSpace() == false &&  DateTime.TryParse(value, out dt) == false)
             {
                 yield return new ValidationResult(string.Format("The string value {0} cannot be parsed into a DateTime", value),
                                                   new[]