I'm really happy with the Reporting Services team. I've had a few items on Connect where I've asked for features and they've come back and said "Done!".
One of these is RenderFormat. I wanted the ability to change my formatting based upon where I was rendering to. For me, this came from a need to have quite different output when rendered to Excel than when rendered to HTML or PDF.
Now, there is a global variable called RenderFormat that allows me to use RenderFormatName in expressions. Woohoo.
But the good part is they went further. The team realized that some decisions are simply based on whether or not the target is an interactive one or not ie: perhaps I want a very different page length for HTML than for PDF. They added RenderFormat.IsInteractive to allow us to test for this.
Thank you Reporting Services team.