According to today's WSJ, Mozilla's FireFox browser has gone for 19% market share last June to 22% last month.
"The most recent version of FireFox, released last June, makes it much easier for Web surfers to return to a site they've previously visited. They won't need to know the site's address -- the browser's address bar offers what's essentially an automated bookmarks list.
This is likely to reduce the number of search queries per person over time. People frequently use search engines as a de facto address bar to find a site they visit repeatedly but haven't bookmarked."
The above feature is not enough to build or sustain momentum, however. FireFox is cooler than Internet Explorer, which may be.