SharePoint 2007 has built-in support for Resource files helping you achieve localization. Using these files you are able to set localized labels for the resources being provisioned. Furthermore you are able to use Resource files within your assemblies to support localization on run time. Yet there is something wrong with localization in SharePoint 2007...
Visual Studio 2005 extensions for Windows SharePoint Services 3.0 (VSeWSS) ship with a useful tool called SharePoint Solutions Generator. One of its features I use most often is creating a List Definition based on an existing list. Since the CAML schema of a list isn't really straight-forward - especially if the list uses complex settings and multiple custom views it's almost undoable to create such schema manually. Another possibility could be using List Templates instead of List Definitions. List Templates are unfortunately impossible/difficult to customize and should be used, in my opinion, in SharePoint configuration scenarios when there is no other choice. SharePoint Solution Generator comes very useful if you want to work with List Definitions but you don't want to type all the CAML yourself.
While working with the SharePoint Solution Generator (a utility which ships with Visual Studio 2005 extensions for Windows SharePoint Services 3.0) I have stumbled upon an interesting by-design feature which affects the way you develop Features - at least if you're using or planning to use the SharePoint Solution Generator (SPSolGen).
A SharePoint 2007 development can get quite complex depending on the business case and requirements of your customer. Last year I have worked on a few SharePoint 2007 solutions. During the development I have noticed that it is extremely helpful if you know how the customer's infrastructure will look like. It will help you even more if you will configure your development environment to resemble the customer's infrastructure as much as possible.
Designing and developing accessible web sites on top of SharePoint 2007 gets more and more attention in the community. But the more developers try to reach the required accessibility or standards compliancy level, the more challenges they face and the more questions pop up. One of such questions is which doctype should be used for standards compliant and accessible web sites.