My first thoughts when reading about Chrome Frame in one of Google's developer newsletters, was "Awesome we can now ditch support for IE".
IMHO I feel that as a development community we should simply not support IE, but according to W3Schools stats on browsers http://w3schools.com/browsers/browsers_stats.asp we're still looking at about 39.3 % of all internet users running IE, so as a Businessman I need to look at things from a WHO IS PAYING perspective and from a ROI perspective, also the purpose of the website or application in question makes a huge difference on which browsers to support. A corporate venture could not afford for 39.3 % of their potential clients simply not being able to navigate and view their site.
Chrome frame will be great if people actually install it, but in reality, end users who have not upgraded from IE6 and who are not using Fire Fox, Opera, Chrome or Safari yet are not likely to install Chrome Frame as they would probably not know how to install flash or Java Runtime either.
I guess at the end of the day to support Chrome Frame, one needs only support Chrome and then add the additional line of code to your pages initialising the Frame if it is installed.
But we will still need to support IE, at least 7 and 8 for those users who are on corporate networks or work for narrow minded organisations that don't allow Open Source standards based products on their IT infrastructure or who are simply not interested in allowing users to control their own web experience.
Browser support boils down to your web site's target market, which I see as follows:
- Corporate Informational/Portfolio/E-commerce Site - Open User Group - Want to sell something, product or service. Generally you will need to support more browsers as you are not sure what your potential customer may be using and your site should look good no matter what they are using. For example a shop selling flowers online, is not in control of who visits the site and the end users environment, if a visitor working at a commercial institution browses to the site or finds it in a seach and wants to buy flowers for someone and the site does not support IE then the flower shop will no doubt lose the sale to another site that does support IE. Also anyone searching for information on a product or service, from work where the environment is restricted and are forced to use IE, would not get benefit from a site that does not support IE and would be forced to look for services/information from someone who can provide them access to the information while they are looking for it in the format that they are able to view it.
- Web Application - Closed User Group
Once you have agreed on a browser, focus 100% on making your app work in it and don't' worry about other browsers at all. Learn all the browser specific optimisation tricks and features that you can leverage from in the development language that you are using, so that when you do launch the app it will be really fast and look good.
If you choose, FF or Chrome, I would recommend you consider building an extension/plugin, that runs in the browser, this way you can leverage more client side processing and have faster access to features, by running the some of the features natively from within the browser. Also building plugins for an Open Browser can usually be done using XML or JS so you're probably already fluent in either of these languages if you are building a web app for a commercial venture.
- Personal Blog - the world
Depending on whether you are one to make a stand or not and whether you care if users can see your site in different browsers, I think support the open ones and then redirect IE users to http://abetterbrowser.org/ automatically.
I haven't got to that point yet for my own site, but will probably implement that soon, as I think it is good to let people know that their are more browsers out there and you can do so much more with an Open Source one.