I just started playing with it but these are the things I did notice right off the bat:
(taken from the release notes)
Thumbnail interaction. Now you can click on links immediately after the page loads without having
to zoom in. This enhancement is especially helpful for high resolution phones, and for familiar sites
where you know right away where you want to click. It makes getting to the content you want on
the page simpler, quicker and more efficient.
Improved zoom. Double-tap or double-click to zoom over any element, including links, images or
videos. The zoom interaction is smoother and more responsive as well. Best of all: when you zoom
in you will get readable text instantly.
Enhanced navigation. When you navigate back or forward, you return to the last viewport (e.g.
zoom level and portion of the page). This eliminates the need to pan and zoom into the section you
were viewing on the previous page. Skyfire remembers the viewport even when you select a page
from your history. We have also added shortcut keys, (9) for forward and (7) for backward
navigation.
Improved page handling. Enhancements have been made especially for AJAX-intensive sites such as
Facebook and Gmail. When larger parts of the page get updated, the client will more quickly and
accurately reflect this. In addition, now, we support full-width iFrames in Skyfire.
Fast start. We changed both the sequence and behavior of the Skyfire launch so you get started as
quickly as possible. You can type a search or URL in the Superbar while Skyfire is connecting in the
background. You can put Skyfire to work before the start page is even loaded. Plus, we’ve impr
oved
connection performance.
Read the release notes here.