This started off like one of R.A. Lafferty's Retief novels, but then switched gear to a more conventional save-the-planet thriller. It's not quite a comedy, but there is some sassy banter between the leads, Harry and Robin, that sets a lighter tone.
Scalzi has fun with his competing agencies (modelled on the US), complete with competing villains, and his nods to Philip K. Dick and others. There may even be a nod to Heinlein's Stranger in a Strange Land in there.
It's a very net-connected world, somewhat overtaken by events (the notion that IBM will continue be a major computer manufacturer looks ever less plausible), but the cyber-security rings true-ish, being over-simplified for the sake of the plot.
Guns, monsters (well, aliens) with a conscience, heroines with attitude who nevertheless needs rescuing, veterans of a military snafu, AIs, galactic politics are all there. Of the minor charaters, I did like Judge Bufan Nigun Sn, and his refreshing court-room manner.
Weaknesses were few (or at least, minor). The activity at the mall felt contrived, with a sudden piece of new technology that moments later becomes the deus ex machina in the crisis, and marks the transition of Harry into action hero. The flip-flop nature of Robin. The confusing number of villains. The computer technology of the Nidu. Oh, and the hero's name, just begging to be used in a weak joke (it is).
The only other Scalzi novel I've read so far had been Old Man's War, and for me The Android's Dream is more adventurous and more original. That said, while the journey held more surprises, the destination was the usual one. Humanity is once again saved, and a jolly thrilling romp is enjoyed while we get there.