One of the central physics issues currently targeted by nonlinear gyrokineticsimulations is the role of finite-β effects. The latter change theMHD equilibrium, introduce new dynamical space and time scales, alter andenlarge the zoo of electrostatic microinstabilities andsaturation mechanisms, and lead to turbulent transport along fluctuatingmagnetic field lines. It is shown that the electromagnetic effects onprimarily electrostatic microinstabilities are generally weakly ormoderately stabilizing. However, the saturation of these modes and hencethe determination of the transport level in the quasi-stationary turbulentstate can be dominated by nonlinear electromagnetic effects and yieldsurprising results. Despite this, the induced transport is generallyelectrostatic in nature well below the ideal ballooning limit.