Yosuke Okunari, producer of the Dreamcast remakes, told GAME Watch (translated by Andriasang) that Sega might consider Saturn games in the future, though it's a different initiative from the current releases. "What we announced this time is a project where we will have consecutive releases of titles that were debuted on Dreamcast," he said. "Separate from this, we're of course thinking about ports of Saturn games. It's the same as how Sega Ages and Virtual Console were separate existences. It's not that we have no intention of porting Saturn titles, so please share your requests." Sega Ages was a series of disc-based PS2 rereleases of classic Sega titles.
Coincidentally, the NiGHTSintodreams.com fan community sent out an announcement today for its campaign to convince Sega to port NiGHTS Into Dreams to modern consoles, in honor of the game's 15th anniversary. As one of the most prominent first-party games, NiGHTS has a good chance of being one of the first releases, should Sega decide to pursue Saturn ports.
[Update: This post originally referred to the XBLA Virtual-On Oratorio Tangram as a Dreamcast port. It's actually a port of version 5.66, which was released as an arcade game after the Dreamcast version.]