SharePoint forms authentication

My question is about the future of SharePoint forms authentication. 

I have heard from few techies that forms authentication is not a good solution as we need to modify web.config files for it to work and it stores user info in a SQL DB (at least I think this is a popular option). 

So If I am looking for a good long term reliable solution through which I can give external users permissions to SharePoint then what is the recommendation. Did I get the info about forms right in the first place. Considering the Microsoft vision for SharePoint,, is SharePoint forms authentication a good viable solution?. 

@R