I'd say it's still the 110. I would bet it's sales are still strong, and if you throw in the near infinite number of clones you have a knife used in a lot of places.
There are two ways, however, to respond to this:
--which knife best fulfills the role of the all purpose knife?
--which all-purpose knife is the best seller, is more universal?
The op asked "which is the most popular now", so here goes:
As to newcomers, I'd guess the Delica or Griptilian outsell most other offerings from Spyderco/Benchmade/Kershaw.
If overall popularity/sales is the criteria, getting past the saks, I would guess something from Gerber. The big sporting goods chains (with their huge orders and sales) swear by them. Even rEI is big on them.