So by now I'm sure you are aware of the Service Packs released for Windows XP and Windows Server 2003!

If you aren't, check out the following links:
http://msdn.microsoft.com/security/productinfo/xpsp2/
http://www.microsoft.com/windowsserver2003/downloads/servicepacks/sp1/default.mspx

So the Service packs are built on the following Security Pillars; Network, Email, Web, Memory and Maintenance

How will I be affected as a Developer?

Windows Firewall - This is a stateful, inbound filtering firewall. If your applications are listening for inbound connections and are not configured to run against the firwewall...you may experience problems.

RPC - All remote anonymous calls will fail. Only processes running as Local System, Network Service or Local Services can open ports for RPC.

DCOM Enhancements - The main problems you will experience, are if you are trying to issue remote calls, but as an anonymous user. Most applications will run as long as you are an authenticated user.

Memory Protection - The DEP (Data Execution Prevention) and Execute NX (If CPU supports this) will make a best endeavour to protect you from common attacks in and around Buffer Overruns.

Email Attachment Manager - Set of APIs which will add enhanced security for mail attachments. Threat of email attachment viruses minimized.

Enhanced Browser Security - All files processed by IE have additional security. IE now has a pop up manager which will prevent unwanted pop-ups.

Improved Computer Maintenance - Microsoft Windows update supports updates to applications such as Office and SQL Server as well as Windows.

What about Visual Studio?

VS2005 and .NET Framework 2.0 work out of the box

Earlier versions you will need to be running the following Framework versions: Fx 1.1 SP1 and Fx 1.0 SP3

What about SQL Server?

1. Use the SQL Server, Server Network Utility to determine the protocols and ports used
2. Enable networking by using one of the following:
   Add the TCP port as an exception (normally 1433)
   Add the SQL Server program, sqlservr.exe, as an exception
3. Use named pipes and add port 445 as an exception

This not a complete list, just some of the more prominent features. Please review the highlighted links above for a more in-depth review.