Just download it and have a look at the description of what it does, and you'll have a pretty good idea about how archery will be in Skyrim. Just quoting two features that directly affect backwards running:
"-Moving around will make you miss (shoot off the cross hair) a lot. Running or jumping is worst than walking. This is reduced by holding still for a few moments. There is an optional Bobbing bow sway effect that visually tells you when momentum is no longer effecting your shot after moving or jumping.
-Moving backward has RISK! This is NOT a random event. My mod detects tripping hazards! You may trip over the dead, change in elevations like stairs or large world objects that interfere with your movement such as a chairs!"
If that's how archery is in Skyrim, I will be extremely pleased. Combined with the more powerful bows, this will make for a much more useful Marksman skill without it being overpowered. Very realistic. I love it!