A FIRM BELIEVER in clean slates, new leaves, and the cycle of life, BizTips would like to ring in 2004 with three new arrivals in the whirlwind world of dining out. Up in Noe Valley, the long-suffering China Pepper has given way to Long Island Restaurant (1689 Church, S.F. 415-695-7678), a purveyor of Szechwan and Hunan cuisine. Northward, where Japantown abuts Pacific Heights, we'll meet no more at the Meeting House, a space recently taken over by Quince (1701 Octavia, S.F. 415-775-8500). And near the waterfront, where the Cypress Club once sat in atmospheric state, the plainly stated and seafood-rich 500 Jackson is now taking reservations.