Old news by now, but SP1 is out with all sorts of glorious new features, except a good installation path. If you have several machines to update with both VS2008 SP1 and .NET 3.5 SP1 (e.g., a team), you’ll want the ISO file, which can be tricky to find. Direct link to combined installer .iso. And, I use the awesome freeware ImgBurn to create the disks for my team.
I’ve seen a couple reports that the installation takes 3+ hours, but all told installation for me went 45 minutes. I cheated, and downloaded the .NET 3.5 SP1 first (full package at http://download.microsoft.com/download/2/0/e/20e90413-712f-438c-988e-fdaa79a8ac3d/dotnetfx35.exe), installed that, then ran the combo installer.
Greg has a great list of VS2008 things to download (including the MSDN update and training pack) at http://coolthingoftheday.blogspot.com/2008/08/visual-studio-2008-net-35-sp1-etc.html.
As always, make sure to remove any previous betas of the SP (both .NET and VS) you have installed. I had the SP beta installed, and got rid of it from Add/Remove programs before I installed anything. If you have any hotfixes installed, you need to remove those as well. This time, there’s a hotfix removal tool.
Unlike Craig Shoemaker, I was not asked for the original media. I installed the MSDN updates, too, which tool a little over 30 minutes themselves. All told, you’re investing a couple hours for a full update.