Super Mutants, Bark Scorpions, and other Fallout: New Vegas baddies always get the jump on me. It's not because I suck--it's because I run backwards. I've discovered that if you jog while facing companions, it's easier to keep track of them and recover them quicker if they get stuck on geometry (which happens quite often in the wastelands). Obviously, this is not an ideal way to play New Vegas, but it's just one of those things you have to live with if you want to enjoy the fun, yet buggy game.
Better and more forward-facing times are on the horizon I'm assuming, as Bethesda has announced a big 'ole "comprehensive" patch for all three of the game's platforms. According to a recent Bethesda blog post about it, Bethesda mentions that the patch will squash save file corruption bugs and address a "number of other issues being reported" by people. Surely, companion glitches have been brought up to the studio often enough to be fixed with this one, right? Fingers are crossed.
This patch is expected to arrive in a few weeks, as it exits final testing and hits certification. A different and smaller PC-specific patch that will address companion woes, save corruption issues, and improve NVIDIA owners' performance problems is expected to drop as early as next week.