Honestly SP1 doesn’t seem to be a major release compared to previous SPs we’ve seen but there are still some interesting changes.  Here’s my highlights.

• Non-browser based help –  If there is absolutely one feature that caused an uproar during the betas of VS 2010 it was the new help system.  The help team took a serious beating while trying to justify the new system.  For better or worse we have to live with the results.  One of the big friction points was the reliance on the web browser and online help.  Fortunately before final release MS fixed things so we could have offline help but we were stuck with the browser.  Fortunately the group at Helpware Group remedied this with a client UI for viewing help files.  Albeit it wasn’t the best tool and it seems like a new fix was available weely but the group really did a great job and they stayed vigilent. 

  Fortunately with the release of SP1 they no longer have to do this as MS has included a client UI for viewing help files.  Hopefully MS has learned a valuable lesson about developers and their help system and, in the future, will not make such sweeping changes without first getting feedback.

• Silverlight 4 –  Sure you could download the SDK separately but now it is included. 
• Docking window crash – How long has VS supported docking windows?  How long has multiple monitor support been around?  Evidently nobody at MS does any of this because the RTM version of VS2010 crashes if you dock/undock windows while debugging.  Fortunately MS fixed this with a hotfix and now it is available in SP1.
• IIS Express – What, never heard of IIS Express?  It is basically IIS bundled by itself and usable on client machines without all the headaches and issues of IIS.  Read about it here.  SP1 introduces support for IIS Express.  I suspect that most devs will migrate to it and that WebDevServer will quickly go away given all its existing limitations.
• x64 Intellitrace support-  SP1 now supports using Intellitrace in x64 builds.  Note that this doesn’t mean you can do Edit and Continue in x64.  That issue still remains but at least x64 is starting to get the love.

UPDATE:  A couple of notes.

1. SP1 can be installed over SP1 beta.
2. Remember how long it took to install VS 2008 SP1.  Plan for the same hour or so.  This time it just takes that long to install rather than taking 20 minutes to extract the files like it did in VS 2008.