> The best argument I've ever heard for cross-browser compatibility broke
> the debate down to simple numbers.
> 
> Assumption: 70% of all Internet users use IE.
> Assumption: There are 100,000,000 Internet users online.
> 
> Conclusion: If you only code for IE, you're automatically ignoring
> 30,000,000 potential customers.

There is no link between the first two assumptions and the last. You are only ignoring 30,000,000 potential customers if the distribution of browser types across your customer base is the same as the distribution of browser types across the world. This is unlikely to be the case. For example, if someone uses Lynx, they are unlikely to use the web to obtain products and services.

It must also be borne in mind that the cost of developing a cross-browser application minus the cost of developing an IE-only application divided by the number of non-IE customers must be greater than or equal to the average profit generated by non-IE users over the lifespan of the site being developed for it to be viable in a business sense.

> All of the sudden, 70% doesn't sound like a lot.  ;)

In certain circumstances far less than that would be enough to justify an IE-only solution :)

Regards

Chris Marsh
