I think the portrayal of women in video games has made considerable progress, but it's not a unified progress. Much has to do with the fact that portrayal of characters in videogames has made a significant progress, so much more can is done with characters now than 10 years ago. There is a huge gap between the sexes, with males being given much more attention and females given skimpier outfits, but we also see some games that really take equality as an issue.
Take Half-Life 2 for instance. Sure, the cast is 5 males (since Episode 2) and 2 females, but Alyx can almost count for 2 for the amount of attention that is paid to her. The resistance also features males and females fighting side by side, a not very common sight. The girls in HL2 are not given any more or any less weight than the guys. A very equal game.
Another game that pops into my mind features an all female cast; Portal. Granted, there are only 2 real characters in Portal. Glados and Chell. While Chell is just a shell character for the player to fill, GlaDOS is one complex girl, with no skimpy outfits or sexual behaviour. Oh, and the gunturrets are ladies too. Imagine that.
I believe that the gaming industry will be male-centered for a very long time. It's not going to change very quickly. But as long as quality studios such as Valve at least consider the equality issue, we'll be seeing many quality games with at least somewhat equal females. And I believe that that will lead to better games and more gamers.
I also belive that as long as the gaming industry is primarily focused on males, and girls are not the ones making the games, we'll be surrounded by sluts in skimpy outfits. Which some may find to be a good thing.