The 20th century analytic tradition is often thought to have been
initiated by Frege. My general question for discussion is the
following...

What key concerns in Frege signify a distinction between him and those
philosophers who preceeded him? What is the analytic turn in
philosophy? What has been lost or gained by this move?

My own input will revolve around Frege's contributions the foundations
of mathematics.

Frege took it upon himself to free arithmetic (not geometry) from
Kantian intuition and to reinstate the idea of rigor and definition in
the foundation of mathematics. The rejection of the former and the
appeal to rigour and definition was motivated by the assumption that a
proof in mathematics does not proceed by intuition, or any appeal to
experiences, but rather proofs proceed logically. Their steps should
be laid bare to remove any mystery from the notion of a proof. The
importance of this move recieves support because of the problems and
confusions with the introduction of the calculus.

Kant assumed that there was an intuitive component to the concept of
number. That is numbers are not concepts of pure understanding. The
intuitive content appears when applied to other concepts, for example
'7 pieces of chalk'. This concept has a definite intuitive component
for Kant involving the process of iteration (1 piece 2 pieces....)
which takes place in time. Frege wanted to show that arithmetical
claims had no intuitive content.

Frege and Kant both agreed that logical concepts were concepts of the
pure understanding. Frege hoped to show that aritmetic was a
consquence of logic, and as a result a concept of pure understanding.
In order to do this he required a greatly expanded notion of logic
(until that point the only logic was aristotlean logic, this is not to
ignore work done by medievils and helenistics, but logic really was
understood as what appears in aristolte). It is here that one of
Frege's greatest contributions arises. Frege's logic is the forerunner
to what we now know as classical logic. In Frege's system all of
aristotle's logic could be accomodated in a small fraction called the
monadic fragment but of course grew to accomodate much more than this.
We can talk about n-place relations, functions and quantifiers. And
most important arithmetic, it could express formulas only satisfied in
an infinite domain.

Though Frege's work sadly ended in contradiction (feel free to ask for
more details)- due to Basic Law V + his assumption about extensions of
concepts themselves being objects in the domain of individuals- a
great deal of productive work resulted from his basic insights(See
Russell, Wittgenstein, Ramsey, and many many others). The question
still remains, should we think of arithmetic as being merely logical
in character (i.e. mere rule manipulation) or is the a kind of
intuitive content to aritmetic?