We compute the conserved quantities for some classes of anti-de Sitter and de Sitter black hole spacetimes in diverse dimensions. The quantities in dS spacetime match with those in AdS black hole spacetime but when the horizon of the latter is a Euclidean (hyperbolic) space. This led us to conjecture that de Sitter holography is mapped to an AdS space whose boundary is a constant negative curvature manifold; the latter space normally breaks the supersymmetry as does its de Sitter counterpart.
We also present some smooth time dependent supergravity solutions that correspond to analytic continuations of Kerr black holes.