We estimate how well we will know the parameters of solar neutrino
oscillations after KamLAND and Borexino. The expected error on Delta m^2 is few
per-mille in the VO and QVO regions, few per-cent in the LMA region, and around
10% in the LOW region. The expected error on sin^2 2theta is around 5%. KamLAND
and Borexino will tell unambiguously which specific new measurement, dedicated
to pp solar neutrinos, is able to contribute to the determination of theta and
perhaps of Delta m^2. The present data suggest as more likely outcomes: no
measurement, or the total pp rate, or its day/night variation.Comment: 12 pages, 4 figures. v2: comments and references added, final versio