Emirates would be a great addition to Boston. A great product, a growing route network that will be extremely attractive through a non-restricted hub in Dubai. Not to mention they serve quite of few destinations that other carriers don't.
I'm guessing they'll focus on adding Chicago, Washington, and Miami first before Boston. I believe Emirates plans to add 4-5 more U.S. cities in the next few years. Would the 787 be what would get Emirates to Boston?
If Boston could get Korean Air to Seoul, ANA or Delta to Tokyo, and an airline like Emirates to Dubai/Middle East, flying out of Logan will be very attractive and a great carrot for businesses to come to Boston.
I don't really see JetBlue gaining anything from going into any other airports and going head-to-head with Southwest (and I think the Florida market is really the only thing they could go after). Not to mention the costs to open a new city, dedicate aircraft, and the manage the service and the airport station costs. Better off building up the hub out of Boston.
JetBlue has been a god send for Boston in a lot of ways. The legacy carriers, battered financially, have been retrenching and shifting a ton of capacity to their hubs, instead of point 2 point routes. Boston, while it is a massive air market, the 10th largest based on domestic numbers, has seen airlines like American and Delta trim schedules. American used to fly non-stop out of Boston to places like New Orleans, Ft. Lauderdale, Orlando, San Jose, Las Vegas, Seattle, Norfolk, VA, those have all been cut in the last 5-6 years. JetBlue has stepped in an really built Boston into a solid hub for them.
JetBlue continues to build on partnerships with foreign carriers such as Lufthansa and that can only mean good things for Boston. If JetBlue were ever to join an alliance and that may very well happen, that will only be an added benefit to Boston.