What? The standard naming procedure for an update to a shipped Microsoft product has been since, oh 1995 at least, a Service Pack or SP for short (except Office, they used Service Releases for a while, but have "corrected" that mistake). Service Packs start at SP1 and go up from there until Microsoft decides to stop releasing cumulative updates containing all the hotfixes that exist for that product. Another exception is when the first public release of an SP is bugged, then they append a letter, like SP1a. So what is going on with the Visual Studio version number? It appears I might have a Service Pack installed, but which one? Why do I have to Google which Service Pack I have installed? Does this Visual Studio 2005 SP1 landing page inform me how to tell if I have it installed? No. The release notes? No. What's New? Try again. How about the download itself? Ah yes, I have to match up the version here to the one in the Visual Studio 2005 About dialog. Crazy. It took me 5 minutes to dig through links looking for a clear-cut way to tell.
This isn't just a Visual Studio 2005 problem either. Here is the huge About dialog from SQL Server 2005 Management Studio:
Maybe dumber, just version numbers of various components. If you are going to use terminology like Service Pack or the abbreviated SP, you should always have it in your About dialogs. What is so hard about doing even this simple thing consistently?