What is personal genomics?

Wikipedia calls it as

"Personal genomics is the branch of genomics concerned with the sequencing and analysis of the genome of an individual. The genotyping stage employs different techniques, including single-nucleotide polymorphism (SNP) analysis chips (typically 0.02% of the genome), or partial or full genome sequencing. Once the genotypes are known, the individual's genotype can be compared with the published literature to determine likelihood of trait expression and disease risk."

the irony of the matter is that no one man is an island. 

The allure of personal genomics is invariably the ability to use something like a tricorder or minION to collect data about your personal genome and suggest an action for you, specific to your genome, so that you may act on the full potential of your GATTACA. 

you might have been told how special you are. One in a billion. To make sense of what your genes are saying, you actually need to find rare individuals in sufficient quantities to make a statistical inference that the bunch of you who share this variant in your DNA that predisposes you to a XX% risk of being an XX person. 

the (100% - XX% ) chance of you being otherwise is often not explained well enough. Where would you find this missing variability? 

There's epigenetics which i would argue is more PERSONAL genomics than the PG offerings out there. These variations account for the environmental impact that is quantifiable by genetic testing. Most tests are research use only I presume. 
There's structural variations which potentially affects the genome more than SNPs, and trying to predict the phenotypic effects of SVs will probably plague the next generation of bioinformaticians and geneticists.
There's also the rare variants which may explain the missing heritability 
Then there's the very intimate microbiome which consists of microbes that may hold an entirely different genome from you but affects your health in such a strong way that I think personal genomics should include this category.

 So while cheaper sequencing technologies has enabled projects like The Personal Genome Project (PGP) or deCODEme.com there's still a lot more to YOU than what your genes say about you through SNPs. 

That said, I am happy to genotype my SNPs with 23andMe kits or a kit from Xcode Life Sciences  to make an informed decision on maximising my exercise potential (and minimising the harm), but I need to be mindful to not ignore there's stuff that I may not carry personally but can make me into a roadkill statistic (1 in the 6426 ) or suffer an heart attack as a result of a stupid co-worker ... 

Live long and prosper , don't sweat the small stuff. (unless they are rare and have a combinatorial effect greater than its sum)