We have a list of complicated things, which the user can click on to get a new view in which they can edit all the details stored for that thing.

The edit view already has a Cancel exit mechanism (default for all our edit forms) and it has a save button (which both saves and exits back to the list).

Should the Save button be disabled until changes are made to any of the details?


Question: "Obama is in town this weekend" or "Obama will be in town this weekend"
Answer: The present tense is often used for future events that are scheduled:


  Did you know that Obama is town this weekend?
  
  Really, when does he arrive?


Aarts in Oxford Modern English Grammar (p248) calls this the present futurate, and lists I start my degree course next week as one of his examples. He goes on to explain:


  It would have been possible to use other means of referring to the
  future in these examples, but with the present futurate the future
  situation is anchored in the present, and in some way scheduled to
  take place as a 'diaired occurrence' or as a natural occurrence. The
  use of the present futurate makes the conversation more lively by
  bringing the anticipated situation to the fore. Notice that for these
  examples to be interpreted as futurate uses, a time specification is
  normally required.


As an aside, it is worth noting the inherent ambiguity of the statement Obama is in town this weekend if said on a Saturday. It could mean that Obama is here now, or it could mean that he is arriving later today or on Sunday. Obviously, if the statement is made on a non-weekend day, then it can only be referring to the future.