Here is how I imagine such scenario:
1. You should be having two custom controls, based on NewsView.
1.1. The first one will form the Full Urls (details URLs, the one having the tags in the query string). It will also be able to extract the tags related to the each content item. Let me know if you need help with this control.
1.2. The second one will be able to read the tag collection from the query string. Тhen here comes the different part
2. The tags cannot be used in FilterExpression more than once. That said, if you filter by several tags, only the last one will be counted. This is going to be resolved in the 4.0 version.
What you can do except using a second NewsView control is to build a custom control which will show the titles of the news only. For that purpose you should iterate through the News items and use intersection - a collection with items having every tag you need.
the Telerik team