“Pokemon” fever seems to have abated in the U.S. about five years ago. But it’s still generating lots of heat in the vidgame realm.While American kids’ obsession with the Japanese trading-card and cartoon creatures largely faded — the last “Pokemon” movie to get a U.S. theatrical release, 2003’s “Pokemon Heroes,” grossed less than $1 million — “Pokemon” remains a hot videogame property. In the first half of the year, Nintendo’s “Pokemon Diamond” for the DS was actually the best-selling game in the U.S., moving 1.67 million units. The No. 3 game? “Pokemon Pearl,” also from Nintendo for the DS, sold almost 1.2 million units. That’s nothing, however, compared with Japan, where the “Diamond/Pearl” duo has sold 5 million-plus units.