Criando Testes de Interface em .Net com Selenium WebDriver para a aplicação NerdDinner

CadastrarDinnerTeste.cs

using System;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading;
using NUnit.Framework;
using OpenQA.Selenium;
using OpenQA.Selenium.Firefox;
using OpenQA.Selenium.Support.UI;
using OpenQA.Selenium.IE;

namespace SeleniumTests
{
    [TestFixture]
    public class CadastrarDinnerTeste
    {
        private IWebDriver driver;
        private StringBuilder verificationErrors;
        private string baseURL;

        [SetUp]
        public void SetupTest()
        {
            driver = new FirefoxDriver();
            baseURL = "http://localhost/NerdDinner/";
            verificationErrors = new StringBuilder();
        }

        [TearDown]
        public void TeardownTest()
        {
            try
            {
                driver.Quit();
            }
            catch (Exception)
            {
                // Ignore errors if unable to close the browser
            }
            Assert.AreEqual("", verificationErrors.ToString());
        }

        [Test]
        public void CadastrarDinner_QuandoPassarDadosDoJantar_DeveCadastrarEExibirEmLista()
        {
            var titulo = string.Format("Teste {0}", DateTime.Now.ToString("yyyy-MM-dd hh:mm"));
            driver.Navigate().GoToUrl(baseURL);
            driver.FindElement(By.CssSelector("a.logo")).Click();
            driver.FindElement(By.LinkText("Host Dinner")).Click();
            driver.FindElement(By.Id("username")).Clear();
            driver.FindElement(By.Id("username")).SendKeys("teste");
            driver.FindElement(By.Id("password")).Clear();
            driver.FindElement(By.Id("password")).SendKeys("teste123");
            driver.FindElement(By.CssSelector("input.classiclogon")).Click();
            driver.FindElement(By.Id("Dinner_Title")).Clear();
            driver.FindElement(By.Id("Dinner_Title")).SendKeys(titulo);
            driver.FindElement(By.Id("Dinner_Description")).Clear();
            driver.FindElement(By.Id("Dinner_Description")).SendKeys(titulo);
            driver.FindElement(By.Id("Dinner_Address")).Clear();
            driver.FindElement(By.Id("Dinner_Address")).SendKeys("São Paulo, SP");
            new SelectElement(driver.FindElement(By.Id("Dinner_Country"))).SelectByText("Brazil");
            driver.FindElement(By.Id("Dinner_ContactPhone")).Clear();
            driver.FindElement(By.Id("Dinner_ContactPhone")).SendKeys("teste");
            driver.FindElement(By.CssSelector("input[type=\"submit\"]")).Click();
            var textoCadastrado = driver.FindElement(By.ClassName("summary")).Text;

            StringAssert.AreEqualIgnoringCase(titulo, textoCadastrado);

            driver.FindElement(By.LinkText("Log Off")).Click();
        }
    }
}

CadastrarDinnerWithMultiBrowserTeste.cs

using System;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading;
using NUnit.Framework;
using OpenQA.Selenium;
using OpenQA.Selenium.Firefox;
using OpenQA.Selenium.Support.UI;
using OpenQA.Selenium.IE;

namespace SeleniumTests
{
    public abstract class CadastrarDinnerTesteBase
    {
        protected IWebDriver driver;
        protected string baseURL;
        private StringBuilder verificationErrors;

        [Test]
        public void Cadastrar_QuandoPassarDadosDoJantar_DeveCadastrar_e_ExibirEmLista()
        {
            var titulo = string.Format("Teste {0}", DateTime.Now.ToString("yyyy-MM-dd hh:mm"));
            driver.Navigate().GoToUrl(baseURL);
            driver.FindElement(By.CssSelector("a.logo")).Click();
            driver.FindElement(By.LinkText("Host Dinner")).Click();
            driver.FindElement(By.Id("username")).Clear();
            driver.FindElement(By.Id("username")).SendKeys("teste");
            driver.FindElement(By.Id("password")).Clear();
            driver.FindElement(By.Id("password")).SendKeys("teste123");
            driver.FindElement(By.CssSelector("input.classiclogon")).Click();
            driver.FindElement(By.Id("Dinner_Title")).Clear();
            driver.FindElement(By.Id("Dinner_Title")).SendKeys(titulo);
            driver.FindElement(By.Id("Dinner_Description")).Clear();
            driver.FindElement(By.Id("Dinner_Description")).SendKeys(titulo);
            driver.FindElement(By.Id("Dinner_Address")).Clear();
            driver.FindElement(By.Id("Dinner_Address")).SendKeys("São Paulo, SP");
            new SelectElement(driver.FindElement(By.Id("Dinner_Country"))).SelectByText("Brazil");
            driver.FindElement(By.Id("Dinner_ContactPhone")).Clear();
            driver.FindElement(By.Id("Dinner_ContactPhone")).SendKeys("teste");
            driver.FindElement(By.CssSelector("input[type=\"submit\"]")).Click();
            var textoCadastrado = driver.FindElement(By.CssSelector("h2.summary")).Text;

            StringAssert.AreEqualIgnoringCase(titulo, textoCadastrado);

            driver.FindElement(By.LinkText("Log Off")).Click();
        }

        [TearDown]
        public void TeardownTest()
        {
            try
            {
                driver.Quit();
            }
            catch (Exception)
            {
                // Ignore errors if unable to close the browser
            }
            Assert.AreEqual("", verificationErrors.ToString());
        }

        [SetUp]
        public void SetupTest()
        {
            driver = ObterDriver();
            baseURL = "http://localhost/NerdDinner/";
            verificationErrors = new StringBuilder();
        }

        public abstract IWebDriver ObterDriver();
    }

    [TestFixture]
    public class CadastrarDinnerInternetExplorerTeste : CadastrarDinnerTesteBase
    {
        public override IWebDriver ObterDriver()
        {
            return new InternetExplorerDriver();
        }
    }

    [TestFixture]
    public class CadastrarDinnerFirefoxTeste : CadastrarDinnerTesteBase
    {
        public override IWebDriver ObterDriver()
        {
            return new FirefoxDriver();
        }
    }
}

Interessante Diego, eu estava procurando uma solução simples sem ter que configurar o Selenium Grid e sua ideia caiu como uma luva.