There are a few indirect signs that the rumor is correct:
1) An official Austria Sony retailer wrote that Sony will not ship any new [shoplink 3028]Sony A850[/shoplink] models anymore (Source: Sonyuserforum.de).
2) In US there is already a never ending instant rebate on the Sony A900 (Click here to check that on Amazon).
It’s impossible for me to check if there are rebates in all stores in all countries so feel free to check for yourself clicking on those links:
Sony A900 direct links to [shopcountry 3032].
Sony A850 direct links to [shopcountry 3028].