Some web sites can be zoomed by double tap or pinching, but some cannot (try this one: www.sandcmills.co.uk/weather). Zooming works fine for this site and others using the Android's built-in browser but not with FF4. This means that the drop down menus are too small to read and so are unusable. On the built-in browser they can still be used without zooming by using the scroll wheel to get precise positioning for a click, but the scroll wheel seems to do nothing in FF4.