All blade materials represent compromises among different characteristics; there is no "best" at any price. Given that, you have to figure out what kind of blade you want, how it will be used, and what conditions it will face, before you can determine which steel makes the most sense for your purposes.
Titanium is light and it cannot rust, but it is also quite a bit softer than most steels.
Ceramics take and hold an amazing edge because they are harder than steel...which is also why they chip and break far more easily under certain kinds of stress.
Carbon steels are superior in their cutting characteristics to stainless steels, but they will rust if exposed to certain things or if not cared for properly.
Stainless steels are a compromise of rust resistance (although they can still rust) and the hardness, toughness, and other properties we usually associate with a blade.
For most people a good stainless steel is the all-around material of choice for personal carry blades. Everyone seems to have a different favorite, but the most popular high-end stainless steels (meaning the expensive ones) include 154CM (also known as ATS-34), VG-10, CPM 440V, BG-42, and D-2. D-2 is technically not stainless, but it is only 1% under the minimum chromium content that defines "stainless", so it is usually included in that category.
If you look at the BladeForums FAQs there is an excellent article on steel types. Between reading that and hanging around here I am gradually becoming educated on the subject.
--Bob Q
