When I build a team, Garchomp is the only Pokemon I take a hard look at specifically to counter. Things like Salamence are dangerous, but if I build a solid team I usually won't have to worry about it specifically. Chomp, on the other hand...
Right now, I feel like every time I make MUST include a Garchomp, as well, since I'd be gimping myself if I didn't use it. It's just that good.
One thing the original poster didn't emphasize that I think should be mentioned more is Garchomp's speed. There are other Pokemon who have similar attributes but are slow Pokemon, allowing faster counters to get hits in and wear it down. Garchomp is fast enough where only the super elite speed Pokemon can beat it out, and with all it's other amazing statistics that just makes it ridiculous.
EDIT: And for the guy above me, huh? "Make another Pokemon broken and beat Garchomp." How do you propose doing that? It's possible there simply isn't another Pokemon that can possibly be made "broken" enough to "beat" Garchomp.
If anything, in this situation, Sirlin would tell us to abuse Garchomp in every way possible in every team you make.