var list = new ObservableCollection<Dictionary<string, string>>()
            {
                new Dictionary<string, string> {{"name", "Roman"}, {"surname", "Mejtes" }},
                new Dictionary<string, string> {{"name", "Alexandr"}, {"surname", "Lovchev"}},
                new Dictionary<string, string> {{"name", "Dmitriy"}, {"surname", "Tiutikov" }}
            };

            //var pre = list.SelectMany(p => p.Select(i => new Tuple<string,string>(i.Key, i.Value)).Cast<object>().ToList());
            var table = new System.Data.DataTable();
            foreach (var i in list[0])
                table.Columns.Add(i.Key);
             foreach (var i in list)
                table.Rows.Add(i.Values.ToArray<object>());
             Table = table;