This is not the first time a scientist has claimed evidence for life in a meteorite. It was claimed a long time ago for Earth and more recently for Mars. This new paper is interesting because 1) techniques for studying meteorites and possible fossils they are in are more advanced than ever, and 2) An accomplished scientist, Dr. Richard Hoover of NASA, has made the claim of microfossils resembling Earth cyanobacteria in meteorites. (Also, #3, it was published in the online Journal of Cosmology, not in the famous journals you might expect, and the reasons for that are controversial.) Hoover is the Astrobology Group Leader at the Marshall Space Flight Center who is, among other things, recipient of the Gold Medal of SPIE (Society of Photo-Optical Instrumentation Engineers) for his work in extreme ultraviolet optics. Does not getting publication in Science or Nature mean the paper is not solid? Well, Hoover never tried those outlets. Lana Tao of the Journal of Cosmology does not precisely say why he didn't, but repeats some JoC arguments that large journals are distracted by the need to be profitable and that they tend to defend the status quo. I don't think the status quo argument is valid (after all who published the paper naming the controversial "Hobbit" from Flores?) and other criticisms of these journals don't actually say anything about the validity of this particular paper. Neither does Tao's point (in itself quite true) that the big boys have rejected some papers which later turn out to be very important.
I'm not enough of an expert to judge how good Hoover's work is. I'll leave that to others. But he's making a rather Earthshaking claim, and the way he's making it is bound to stir debate - which is, in itself, a good thing.