The thumbnails of tabs dont offer much help when user takes quick look to identify his sites. Maybe only for the very distinctive sites. A circle icon with its logo at 80x80px would help much more I think. This saves space, and opens up the new tab area for app launchers. And also as we see below, there is more room for things like "smart recommendations" like 1) unclicked links from searches user made, and is probably intersted in (this could be source of revenue for fx too) 2) space for predictive new tab like thing: https://addons.mozilla.org/en-US/firefox/addon/prospector-predictive-newtab/

#Step 1, move the new tabs to url suggestions box when blank. Iconify them.

#Step 2, bring in the about:about stuff, this catches html5 apps that addons have registerd to about: pages. Also add ability for users to add native (non-html5) desktop apps to this list.