Since Marvel began Secret Invasion, there have been a few mentions of the Dire Wraiths. The question is, are they building to something or is it all merely coincidence?
First, we have the Skrulls! one-shot. This is from the same group of writers who produce the Marvel Handbooks, but written from the Skrull perspective. It includes a Dire Wraith entry, which is completely understandable since they're an off-shoot of the Skrulls. There are numerous other minor characters featured in this book as well, so by itself this isn't a big deal.
Then, during the Secret Invasion cross-over, two books mention the Dire Wraiths, although none are seen. First, a Skrull mentions them in Runaways/Young Avengers: Secret Invasion #2, basically treating them like the boogeyman. Next, a passing mention of them is made in Black Panther #39.
Now, we have another Handbook-style entry, this time in the Dark Reign Files. I must admit that, to me, this one seems a bit out of place. Except for Volx, no Dire Wraiths have been seen on Earth since Rom left. Why include them in a list of super villains?
Well, one thing to keep in mind is that the Handbook's writers are fans themselves. And most, if not all, of them are long-time fans. So I'm sure that occasionally they put in entries simply because they like them, regardless of whether the subject has appeared recently or is likely to in the future.
From all indications, Marvel has the rights to the Dire Wraiths all to themselves, so there's nothing to stop them from bringing them back. Will they, however, when they can't use Rom as well? You can't really discuss the Wraiths on Earth without bringing him up. Heck, they mentioned him in the Dark Reign Files entry! Obviously, Marvel's lawyers have cleared purely textual references to him. It seems that only showing him in his armor is the big no-no.
My personal opinion is that Marvel doesn't currently have any plans to bring in the Dire Wraiths in a major way. They've just done Secret Invasion, so at this point the Dire Wraiths would only come off as a rip-off of that story. (Even though in reality it's more like the other way around.) It's possible, if a bit unlikely, that their recent Handbook-style entries have been bids to maintain some sort of rights to the name and concept, but I think the recent spate of mentions is largely a coincidence.
(Thanks to Kenny Doug and ~P~ for pointing out the mention in Runaways/Young Avengers: Secret Invasion #2, Sean Koury the one in Black Panther #39, and ~P~ for the entry in Dark Reign Files.)