From this weeks Q&A from other sites:
TheJawa.com: It's unfortunate to hear about the fate of the Titanium Ultra line. Is Hasbro actively looking at other ways of presenting vehicles to collectors that may be impractical to produce in the 3-3/4" scale? Come on, don't you guys remember the Collector's Fleet line?
Hasbro: Fear not about the last few of the Titanium Ultra vehicles…. they will be made available to fans after all, just not at mass retail. Look for details on that soon. As for your other question, we are always looking at new opportunities to keep the Star Wars vehicle program going strong. For now, the focus is on the Titanium 3" assortment, which has a long, bright future as long as fans continue to be an engaged in the format as they have been.