Peter Kuhn solves a problem with the default style for the hyperlink button in Windows Phone 7 which does not wrap the link text.
Source: Mister Goodcat
On Windows Phone 7, some details are wired differently. Often the default templates for controls are heavily simplified due to the lower performance provided on the devices. I recall a statement from someone official (unfortunately from memory as I don't remember where it was) that sacrifices have been made especially in those situations where we have a most prevalent use of certain controls. In this case, the common scenario for a hyperlink is to show a text link, so consequently the default template on WP7 is tailored to text use. That means that those 95% of the developers for Windows Phone 7 that use hyperlinks with text content benefit from an increased performance.