I still think that the old X-Wing & Tie Fighter games from ~1994 are without equal in their genre. X-Wing Alliance was also great. X-Wing vs. Tie Fighter was, well... did I mention Alliance was great?
It's been a long time since XWA was released (1999), so will LucasArts ever satisfy my appetite for a next-gen X-Wing game or has the interest in space combat sims plummeted so far that it's not feasible?
There's always games like Darkstar One, X3, and Freelancer type stuff, but none of these have the allure of a Star Wars backdrop.
P.S. - On a side note, I recently discovered the XWA Tie Fighter total conversion which converts the old TF game to run on the XWA engine. There's also tons of high-res model replacements for XWA. Click here for more info.
To be honest, I highly doubt LucasArts will. They've got a horrible reputation for game making (as far as I, and many others are concerned). Besides, if it's been roughly 7-8 years since they made TWA; you're looking at better odds of winning the lottery before they'll add another to the series.
Unfortunately though, LucasArts holds many (if not all) of the rights to the Star Wars franchise, so there aren't many companies that can develope a new game. On top of that, as soon as they release a game, they make one or two patches just to fix bugs they missed. Soon after that, you lose all support for the game (other than technical), and it's just another box on their shelf.
I for one would like to see a new Jedi Knight game, for I was addicted to JK2 and JK:JA.