1. Is it necessary to mention the date on the recommendation letters, when getting it signed? Can an un-dated recommendation letter be rejected by a university?
Yes it is required. The date should be mentions.According to my experience some universities do not accept an undated letter.
2. If yes, what is the typical duration for which a dated recommendation letter is deemed valid? For example if I take a recommendation letter in Oct 2007 (for Fall 2008), can I use the same to seek admission in say Fall 2000 session OR will it be treated as “too old”?
My experience is that 9- 6 months should be the duration for the validity of a recommendation letter. You will appreciate this if you realize the purpose of a recommendation letter. Univs want to know about your present work and achievements.
3. The question is arising since I believe that I might be able to get better recommendations at this point of time and also that some of the people (both academic and industrial) from whom I am seeking recommendations might move on to some other places after some time. There is a low probability of them retaining the relevant stationary and whether it will be possible or even correct to get recommendations written on some new stationary (of a institute or company with which I had no association).
One solution can be that you get some recommendations with a current date and get a few without dates. With the permission of recommendation writers you can insert the date as per your requirement.
PLEASE NOTE THAT I HAVE SAID WITH THE PERMISSION OF THE RECOMMENDERS.
However the relevance of the recommendation shall again be a question after passage of a time period.
4. Is it ok, if we send the application directly to universities without contacting the profs?
Yes. Professors are contacted to find some compatibility between your area of research interest and the professors area of research. They are primarily contacted for RA.
5. I had sent mails to profs asking them to evaluate my chances of working with them. Some of them haven’t replied. Will it be fine, even if I apply for these universities also?
6. Will applying to 4 or 5 universities be fine or shall I app for more universities?
Depends on your University selection and your objectives of getting only admission or admission along with assistantship.
7. What is the best time to app for getting aid?
NOV – JAN after verifying the deadlines. There is no harm in applying early.