....so the answer is: all of the above (very helpful info, posters, thank you!).
I just re-read the CNN release--guess I was so excited I missed the answer to some of my own questions (doh!) Both of the next 2 launches will be DAYLIGHT, per NASA's self-imposed restrictions; they want to be able to see any falling debris...just in case. (Yikes, how early can "daylight" be?!?!--I am just not an a.m. person...maybe I should drive over at 3am and sleep in the car outside the KSC gates until they open. (LOL!))
Guess I'll plan for a couple of scenarios, and if it doesn't occur on 5/15, I fortunately have a couple of days to work with. As for the traffic, well, it's like that in L.A. every day....person at KSC I spoke to said people generally stop on all the nearby roads/fwys to watch, so it won't be the end of the world if I miss out on the special launch tour (they won't be able to accommodate everyone!), which can only get just so close to the pad anyway. If the launch is scrubbed right before take off or rescheduled altogether, I will certainly be very disappointed, but think that visiting KSC will still be a major thrill, and as one poster mentioned above, there will still be a lot of "shuttle prep activity" going on that will likely be seen in taking the regular KSC tour.
Incidentally, there's another shuttle scheduled to go in July. The windows for both lauches are very narrow and 2nd is essentially contingent on the 1st due to the involvement of the space station in the missions and the safeguards now in place (following the last disaster). The way it's been projected, if the May launch doesn't occur within the narrow window, July launch not likely....If it wasn't as perfect as could possibly be (re: an above post), NASA wouldn't have made the announce, going so far as to pick a specific date this far out on the calendar. (see quotes below; they are hellbent on making this happen this year) Just my opinion, but judging from implied PR concerns, unless something potentially catastrophic is detected and/or the weather is absolutely unseasonal, these flights are going to launch. Just been too much fall out in the aftermath. NASA needs it to happen--as does the nation.
TT
P.S.: To the poster who asked, yes, 5/15 was specifed in the press release; KSC still only lists the range of dates comprising the window.
[from the CNN release:]
"Readdy admitted he hoped the techniques would be further along, but said that two years ago repairing the shuttle's thermal protection system while in flight was thought impossible."
"Both the Discovery and Atlantis missions will be test flights to the international space station to demonstrate the shuttle is once again safe to fly."