You Don't Need to Copy PDB Files to Debug in the GAC!
I generally don't post a link without much else but this was a no brainer and I feel every SharePoint developer, heck, every .NET developer needs to know this. My friend and SharePoint pal, Doug Ware has discovered how to debug assemblies in the GAC WITHOUT having to copy the pdb symbols file to the MSIL folder. In other words, simply attaching to the correct w3wp worker process will work.
It's awe inspiring, I had no idea!
I'm not going to steal his thunder so you will have to read all about here!