[roywiggins]

Sure, there's engineering issues on Mars, but the longest-lasting device anyone's put on the surface of Venus lasted only a couple hours.

Neither are exactly prime vacation spots, but if you want a target for robotic exploration, Mars is so much easier.

[TeMPOraL]

GP has a good point, though. Venus is hostile on the surface, but higher up in the atmosphere the conditions are much nicer, and you could hang dirigibles there. Not interesting if you want to study geology, but very interesting for climate science, and I hear that you could extract enough useful stuff from lower parts of the atmosphere that it could actually be a viable colony spot.