The feature upgrade comes as part of more than dozen security updates for Acrobat and PDF Reader, which were rolled out yesterday in parallel with a new version of the Flash Player software that fixes a critical security flaw.
The Softpedia newswire notes that Adobe has been criticised for postponing patches for Adobe Reader X on Windows on the grounds that the sandboxing technology included in the product protected users against zero-day exploits.
"There is a belief that this type of practice encourages administrators and users to ignore security updates to Adobe Reader X because there were no successful attacks against the Protected Mode", says the newswire.
The new auto-update feature in Reader has also gone down well with security researcher Brian Krebs, show said that, there may be some users who will question the move towards automated updates.
"There is always a contingent in the user community who fear automatic updates will at some point force a faulty patch. But for better or worse, Adobe's Reader software is the PDF reader software of choice for a majority of Windows computers in use today" he says in his latest security blog.
"Faced with incessant malware attacks against outdated versions of these programs, it seems irresponsible for Adobe to do anything other than offer auto-update capability to Reader users more aggressively", he adds.
Krebs notes that Adobe introduced this feature back in April of last year, but at that the time Adobe decided to continue to honour whatever update option users had selected.
With this latest update, he says, Adobe will again prompt users to approve an auto-update choice, except this time the option pre-selected will be `Install Updates Automatically.'