[eluser]crikey[/eluser]
Routes are run in the order they are defined (according to the Routes section of the manual).
Because your first route rule already covers the second one (that is, the first rule will be applied when *any* characters follow 'browse/'), the first rule is applied and the second rule isn't tested. Try swapping the order?
Note: I haven't tried it, but it looks like that's how it works.
Cheers