How to find out the editorial times (for article review) of CS journals? Elsevier has recently lunched a tool called Journal Finder by which researchers can use paper's title and abstract, and field of study to find a suitable journal for their manuscript. Here is the sample 
 in which the editorial time is 12 weeks. They surely maintain database for their own, but is there any other source we can do this for other non-Elsevier journals, like IEEE or ACM? I know WoS provides some information about it, but WoS's database accuracy is not yet clear to me since I have seen lots of inaccurate information in WoS reports (for instance, number of "review article" published is often inaccurate).
Once a year the Notices of AMS publish the backlog of mathematics research journals containing inter alia the data you are interested in. 

The 2012 one is here:

http://www.ams.org/notices/201210/rtx121001473p.pdf

and the 2013 is here :

http://www.ams.org/notices/201310/rnoti-p1390.pdf

and both do list some journals in informatics including the non-Elsevier ones (e.g. the Springer's Acta Informatica).