In the new edition of Popular Photography, they say a new replacement is coming out soon:

“…(the A700) may be an oldie, but it’s still a goodie for its rugged build, fine imaging, and thoughtful design. We strongly suspect Sony will bring out a replacement soon.”

via: alphamountworld

The alphamountadministrators explains very well why this is more than a simple rumor:”For Popular Photography to make such a strong suggestion tells me quite a bit. It’s highly doubtful they would make such a strong statement such as that without some sort of inside knowledge, of which they could not of course confirm nor deny.”

So finally the Sony Alpha 730 is coming soon?