IE7

IEBlog provided a few details on what to expect in I7 beta 1

• Support the alpha channel in PNG images. We’ve actually had this on our radar for a long time, and have had it supported in the code for a while now. We have certainly heard the clear feedback from the web design community that per-pixel alpha is a really important feature.
• Address CSS consistency problems. Our first and most important goal with our Cascading Style Sheet support is to remove the major inconsistencies so that web developers have a consistent set of functionality on which they can rely. For example, we have already checked in the fixes to the peekaboo and guillotine bugs documented at positioniseverything.net so use of floated elements become more consistent.

CyrusN asked What about tabs

Anonymous commented Web designers have clamored for it for years, since they saw what you could do with PNG images' multi-level transparency (now available in every major browser except Internet Explorer, and several minor ones).

Diggory Laycock commented Now we just have to wait another five years so that even "old" machines will be able to render them.

Shetil commented I am glad that IE7 will have png alpha channel support and CSS fixes. This is several good steps in the right direction. The problem is that IE7 will only be available to a subset of all Windows users and it will take a very long time before the majority of users will have a browser with proper CSS and PNG support. I think that Microsoft have mistreated their customers by abandoing IE for years. People that calls this "fantastic" needs to open their eyes. Their reaction is like applauding a student for delivering a paper several years too late.

It looks like IE7 will have some, but not all, of what Firefox has now.