TBS stands for "The Basic School". Although we make fun of it (i.e., Trainees Being Saluted, The Big Suck, Thousands Being Stupid, etc) it is actually a very good concept. All Marine officers - regardless of MOS - go to TBS to learn about all facets of the Corps, in particular infantry. (This also leads to Marine OCS being nothing more than a grueling process of separating the wheat from the chaff by some HARD Staff and Gunnery Sergeants - the real learning process starts at TBS.)
The timeline goes like this upon graduation and commissioning as a 2nd Lt. You wait for your TBS class (some go immediately, some wait for up to 6 months until your class is assigned). 6 months of TBS and then you wait for flight school - once again, sometimes you go straight to Pensacola and sometimes there is up to an 8 month wait. Flight school takes about 1 1/2 to 2 years and then you go to the FRS which can take another 4 to 8 months - finally, you arrive in the fleet. So to answer your question, it takes longer for the Marine to arrive at Primary than the Navy but generally its a good deal because you show up already knowing a bunch of guys and there is a good bit of gouge floating around.
For an example: I was commissioned in June '89, started TBS in Nov '89, started flight school in Dec '90 and winged in Jul '92 - finally arrived in the fleet in Dec '92.
Hope this helps - and wish I could trace places (well, after OCS...)
PS: That's Marines with a capital "M"!