In brief: The first Bernice book I haven't liked. Like a bad Hollywood sequel, the whole book reads like a desperate searching for ideas that were used up years ago.
I never thought I'd say this about a Dave Stone book, but Oblivion's greatest problem is that it's just plain *dull*. Like the author's introduction, the whole book feels forced and painful, as though the author were trying desperately to be clever and funny and failing spectacularly.
Part of the problem is the characters. Bernice and Jason have been in the same room before and managed to remain relatively civil, even if they weren't exactly friends. However here we have to be put through constant bickering between the two, that's no fun for anyone involved (especially the reader). Benny doesn't come across too well from this, but Jason suffers horribly; you'd hardly know this character was the same as the wonderful one the same author created in Death and Diplomacy.
This illustrates a key point about Oblivion: it simply isn't any *fun*. There are some jokes, but they mostly seem to fall flat or worse, are presented as just gibberish for its own sake, like someone at a party saying "Purple Pineapple Hats" for no reason and expecting his audience to titter dutifully.
Chris is much the same, as is Sgloomi, but it's a real shame about Roz. I can understand wanting to do something different with the character, but the early Roz just isn't anywhere near as engaging as the older Roz from the NAs. Indeed, this seems to be recognised within the text, as her character has to be artificially adjusted to become closer to the one we're familiar with. I'm really not sure why: it would have been simplicity itself (given this book's themes) to have Roz simply an alternative one from a dimension where she did survive.
Besides, it's stated that Sgloomi seeks out his human friends whom he knew from previous NAs and also that it's the ones with the most experience of time travel that are needed. Unfortunately (if I've understood this correctly) Roz doesn't qualify here (and I'm surprised there isn't at least a mention of why Ace doesn't turn up). I also think the resolution of her character arc in this book is just plain silly. All this "really" took place in Roz's past, only she doesn't remember. Yawn. Again, why not use the alternate-universe excuse (not a copout in this book)?
The plot, such as it is, is okay, if far too simplistic for my liking (it's hidden under a lot of gloss, but not much actually goes on) The interludes with the supporting cast from Sky Pirates! are *awful*. Like Ship of Fools, Dave doesn't seem to know when these things are boring the reader stiff. There were only four in that book - I lost count of how many turned up here.
Speaking of the Sky Pirates! stuff... well, it's nice to have a summary of the plot of the previous book by one of the characters, but unfortunately Oblivion feels like it's supposed to be Sky Pirates II: The Return. This is unfortunate because it just can't compete with the power of the original; if (like me) you loved that book, you'll probably be disappointed with Oblivion, because it tries to replicate the successes there and fails. However, if you were annoyed by Sky Pirates! you'll probably be even more annoyed by Oblivion, since it has all the irritating bits and none of the sheer glory of the original.
It's not all bad, however. I did like the aliens on the world where we first saw Bernice (it's an idea ripped off from Douglas Adams, but I think it's done much better here) and I liked the Big Sneaky Trick at the end (and it sure is sneaky!). There are also some *really* nasty bits in the alternatives of some of the regulars, especially Bernice and Jason. In fact, if the book had concentrated far more on exploring the alternatives to characters we already know and love (Benny, Chris, Roz, Sgloomi) as opposed to ones we don't particularly care for (Nathan, Leeta, Kiru) it might have been a lot more involving.
I also think Dave's style really damages this book (note: I've never had this problem before in any Stone book, all of which I've enjoyed). It's a little bit sad to see that an author who came to the line with such promise seems to have run out of tricks and instead is desperately trying to rekindle past glories here without realising it was the originality of the ideas that made them glorious in the first place. I can only hope Oblivion is an anomaly, because I'd certainly love to see another book as good as [but not the same as] Sky Pirates! Death and Diplomacy, Burning Heart or Ship of Fools.
In summary, Oblivion is badly let down by Benny and Jason's bickering, Dave's style and a lack of ideas. There are some good things struggling to get out, but I really feel as though I've wasted my time with this one. Not at all pleasant.