This one my friend had was actually closer to a lanyard with a pouch, and I have since found one similar, made by Mayfly.
That Orvis pack looks nice, its pretty big though...I don't usually take much when I fish, but thats usually because the spots I have been to so far don't require much gear to get to or fish. Eventually I'm sure I'll need something like a chest pack or one of those sling packs but till then I'm starting pretty minimalist.
I went to the Santa Ana river over this weekend, and all I took with me was my rod, a box of flies in my pocket, and a bottle of water, and hiked probably a half mile down the river, stopping at pools to fish. I just went back to the car for lunch. A sling/lanyard would have been handy there, but it seemed I didn't or wouln't have needed much more. My friend who I was with at the time wore his vest, and it seemed like overkill.