I recently went from an R10 to a R15. The picture on the TV now appears to be zoomed in and text is being cut off.

Looking for some suggestions.

Is this just on your SD local stations? If so, it's nothing to do with the change from R10 to R15, it's just coincidence. DirecTV used to take SD local signals from the analog SD signals being broadcast by the stations. As the stations start transmitting digitally, DirecTV is moving to receive the digital signals instead of the analog ones. There will be no analog ones after June anyway.
If a station is transmitting an HD 16:9 signal on its digital channel, DireCTV has two choices. Broadcast the 16:9 picture inside a 4:3 frame (pillarboxed) or just take a 4:3 section of the 16:9 picture and use that (centercut). Most stations (all the networks as far as I know) have opted for centercut. It's apparently their choice to make, not DirecTV's.
The 16:9 signals coming from the networks themselves have been adjusted to allow for centercutting. Network "bugs" are now at the edge of the 4:3 from instead of at the edge of the 16:9 frame. Many local stations have adjusted the way they deliver "crawls" for weather and so on so they fit into the 4:3 space. But 16:9 programs that have text all the way to the edges of the 16:9 screen will have the text at the sides cut off.
If it's not the locals, post back and tell us which channels are affected.

check your TV's Zoom rate. look for ZOOM/PSIZE/ASPECT or WIDE buttons