I'm no authority on knives and I don't claim to be. Ive watched my sister's mother-in-law prepare a whole meal with a knife no bigger than a pocket knife. At the same time I've seen Chinese chefs prepare whole meals with razor sharp butcher cleavers. So what do I think is the best knife? Well the answer to that is in your own hands. I personally prefer a nice 8-10" chef's knife to the skinnier carving knife which Thomas Keller has stated as being one of his favorites. My fingers just don't clear the tang when I'm finely chopping up spices. There is an exhaustive list of amazing knife makers who all claim to have the best knives with all sorts of fancy technology, but in my honest opinion no one has better steel than the Japanese. However, unless you're willing to sink hundreds to thousands of dollars into a knife this probably isn't the route to go.
On the road I use a french pocket knife I bought off of eBay (laguiole en aubrac) mostly because I love how it looks and how it holds an edge. It is impractical for preparing meals but for my purposes on the bus it's great. When I'm home my go to knife, the one I reach for first, the one that stays consistently sharp and always shown special treatment is my Henckel 8" chefs knife that was given to me by my mother. She's the original cook in the family and I've learned almost all I know about knife technique and cooking from her. The knife has a nice weight and holds its edge well when maintained using a honing steel before every use.
This brings me to an important topic. Knives should be sharp, not just kind of sharp, but super sharp. It's important to have them professionally sharpened if you don't know how to use whetstones and it should be honed often. Avoid knife sharpeners that you pull the blade through as these just take off steel in jagged pieces and leave your edge uneven and brittle.
There are many many independent knife makers out there who are making beautiful knives that are super sharp and have a great design, seek them out! They are the new world of knife makers and while their price tags are high you will use them for the rest of your life and pass them down to your children and their children. One brand I've been keeping an eye on is Cut Brooklyn. His knives are beautiful and look like they are getting great reviews. I've never used one, but they look absolutely amazing.
My .02 take it for what it's worth.
-joe kwon