Vasp.4.3 is the first ``official'' release of vasp.4.X. One major new development in this version is the support of the PAW (projector augmented plane wave method) proposed by Peter Blöchl. Support is in principle already included in this first release, but a lot of tests have to be done before this feature will be made available to the users (not before mid 1999). The PAW implementation in VASP is based on ideas of Daniel Joubert, only minimal changes were required in VASP to include PAW.
A few changes have been made to some automatic defaults in VASP.4.3: POTIM defaults now to 0.5 instead of 1.0. The number of bands (NBANDS) is now in some cases by default slightly larger the before.
VASP.4.3.5 writes out a nearest neighbor list to the OUTCAR (and OUTPAR file). This often helps to find mistakes in the POSCAR file.