Instead of leaving the user with the front screen
doing nothing, perhaps it could give some feedback as
to what the system is doing during that time that it
is querying. Something listing each site with a status
message: trying to connect, connected, receiving data,
finished sending data, X records returned in S seconds
etc. so that the user knows that something is
happening and it is worth their while waiting for the
query to complete. Of course, improving the response
times at each site would also help.