True, but this ease of use can evaporate once you need to automate the process. Once you're through with the Windows task scheduler and OLE, etc, the effort might end up being the same. (I could be displaying my ignorance here, I'm not really much of a Windows sort -- feel free (anyone) to correct my impressions on this)
You are absolutely spot on that we need a better graphing utility than the GD based solutions floating around. Excel rendering kicks their butt.