thebombdotcom (L337 speak update of the common phrase the bomb) is used in speech (and text) to articulate a persons feeling of being good at something or in general. It can also be used from an onlookers perspective in both a positive or negative connotation, describing a particular attribute the person portrays, or as a general statement.
>> Sean: "I am thebombdotcom"
>> Sean: "I am thebombdotcom at CS"
>> Trent thinks he is thebombdotcom at fighting, but he got rolled by a small bouncer and he stole his money. Haha what a cake!
>> Mike Tyson is thebombdotcom at boxing.