When you compare Firefox to its main competitor, you realize that Firefox faces a huge challenge: being installed on the users' computers.
- To use Firefox, you have first to download it, install it, and then click on the icon. (It's the same for Opera).
- To use Internet Explorer, you just have to click on the icon. Period.
Actually, one does not care that Firefox is Open-Source software, cross-platform, built by a non-profit project, standards-compliant, full of innovative features. Until the user installs Firefox, it does not really exist.
So we have to entice the users to download and install Firefox. Our community is doing wonderful things in this regard, and the 100 millions downloads, the 15% market share in Europe brilliantly demonstrate this.
Firefox will soon be released. We must go beyond these 15%. We must understand that Microsoft is not sleeping at the wheel anymore, but readying IE7, which is going to be quite similar to Firefox. The stakes are the same: accomplish Mozilla's mission: promote choice and innovation on the Internet.
The goal has not changed, but now that Microsoft has put back together its IE development team, now that Redmond's huge marketing machine is going to run at full steam, we, as a project, will have to get ready to respond.
Reaching 10 or 15% was a crazy challenge. But we made it. Now we have to strike back, as IE7 is getting finalized. So we have to focus on promoting Firefox.
The user community must continue its wonderful work with SpreadFirefox.com. We must keep on installing Firefox on relative's machines. We have to keep on talking about Firefox around us, in our families, on our blogs. I am working, with fellow mozillians, on innovative campaigns. Stay tuned 
The Web developer community is also very important for Firefox. This is the reason why I helped as much as I could to get a fix in 1.5 for the One True Layout issue.
The Extensions developer community is also very important, and this is the reason why I did my best so that the Extend Firefox contest is internationalized. (It may not look like something hard to do, but while I was at Netscape, not a single US-initiated contest could cross the borders).
But I'm not sure that all these initiatives are enough. I know too well Microsoft's marketing power to be perfectly calm in the upcoming battle. (Plus, "only the paranoids survive", as puts it Andy Grove, of Intel fame
But there is a ray of hope, when I see a great company standing firmly on Firefox' side just when 1.5 is about to be launched. This is the reason why I have a smile on my face when I read this:
Google Announces Firefox AdSense Referral Program.
Extract from Google's AdSense Support page:
By adding a referral button to your site, you can direct users to (...) download Firefox with Google Toolbar and improve their web browsing experience. While your users learn more, you can earn more (...) up to $1 for every new Firefox user.
For Google, it's a nice way to get more site to advertise with them, while helping us promoting competition in the browser space, and distribute its Google Toolbar at the same time. For site owners, it's an easy way to make some more money. For the Mozilla project, it's a wonderful additional ally in the browser war. Everybody wins. Everybody? Well, almost. I can almost hear chairs flying in Redmond ! 
