Kikuta seems to be going through something of a mini-revival...He's put out a couple of hentai game soundtracks and a solo album called Lost Files, which is basically a bunch of "lost files" of his. Kind of simple synth-rocking stuff, aside from a handful of tracks at the end which could pass for lost Soukaigi tracks (The Lost Island of Souls ones), but I really like it. Sakura Relaxation comes highly recommended if you can find a copy...It was included with the game only and never put out for sale. Very Mana-ish and enjoyable. Lost Files is available at cocoebiz.
Koshiro's main contribution recently was Wangan Midnight 2: Maximum Tune OST, a 2-disc techno/trance album. Not much to say, but if you like real heavy trance, you'll probably like it. Not as pleasantly melodic as his past works, which kind of kept me from getting into it too much.
Iwadare has put out soundtracks for both Grandia 3 and Radiata Stories. Right in that timeframe you described, he did Grandia Xtreme and a solo album, Ingmar. He seems to have slipped as a big name, so you don't hear too much about him recently.
Uematsu has been busy with the Black Mages (rock band doing Final Fantasy covers) and his Blue Dragon OST is set to come out soon. I'm personally looking forward to it a great deal, as he really sounds refreshed coming into it. Also, Black Mages 3 is set to be announced soon.
Shimomura has the OST's for Kingdom Hearts 1 and 2 and will be doing the soundtrack for one of the upcoming Final Fantasy XIII games.
Mitsuda's been kinda busy with smaller releases...He had Hako no Niwa, Kirite and Moonlit Shadow all last year. Nothing major from him in awhile.