This is probably the tip which has saved me the most amount of time recently. When you just want to run a page in the new client, then you don't have to modify other pages to include it, or to make links to this page. Just click Start -> Run, and run this:
In this case, it will open page 90055
This post is based on the Technical Preview version available here (PartnerSource-login required). Obviously, anything might change before the final release. For more information, see this MSDN topic, Creating and Running Hyperlinks.
Lars Lohndorf-Larsen (Lohndorf )
Microsoft Dynamics UK