Still holding out on making the jump from WinMo 6.X, but want the look of WP7? If so, TodayXLive is the app for you. TodayXLive is a plugin for your Today screen that gives you a tile-based start page, complete with live updating. The plugin works for Windows Mobile Pocket PC 5 and 6 and requires .NET Compact Framework 3.5.
Loffactory, the developer of TodayXLive, recommends disabling all Today items that you are not using, so you can save some battery life. If you want to give it a go, you can download it here. (Anyone tempted to fire up their old WinMo device, for old times sake?)