According to article:
" "Today we have decided to withdraw Ground Self-Defense Forces from the Samawah region in Iraq," Koizumi said in a nationally televised news conference. "The humanitarian dispatch ... has achieved its mission."
...
The move to withdraw followed the announcement on Monday that Britain and Australia would hand over responsibility for security to Iraqi forces in southern Muthana province, where the Japanese troops are based"
And:

"Japan will now consider expanding Air Self-Defense operations in Iraq to include transport of medical supplies and U.N. personnel, following a request from U.N. General-Secretary Kofi Annan, said Takenori Kanzaki"

Iraq is becoming more capable of handling their own security and the less troubled regions will be the areas that Iraqi forces will regain control first.

The current focus at the moment, appears to be the capital, Baghdag- depending upon how successful they roll up leads they have recently acquired and how things go in next couple weeks in Baghdag will probably affect how long all coalition forces are needed in Iraq.
As I've said before, Iraq even though it started after Aghanistan, will probably be completed before fighting has ended in Afghanistan.
Because Afghanistan is a narco-state- it's actually has a chance to become a quagmire.
I think the cheapest and fastest way to solve Afghanistan's problem is to simply buy the opium- and aggressively out bid the drug smugglers- if going price is X- then offer 2X.
Then store some place as though it were radioactive waste and/or gold.

In other words Afghanistan will probably be problematic for a longer period than compared to Kosovo whereas though a much larger population and requiring more troops, Iraq will probably be completed much faster than Kosovo.