Recalls have a specific definition: They are coordinated (in USA) through the Federal government and apply ONLY to safety and emissions things and the fix is free for the life of the vehicle.
The next step down is "service campaign" which apparently reflects a defect of such embarassment to the manufacturer that they too are a lifetime free fix. See W210 rust issues.
Everything else (DTB, etc.) are free under warranty (obviously) and owner paid for thereafter. Mercedes does not use the term TSB. You are theoretically supposed to complain before a dealer will perform a free DTB fix, but I imagine some dealers treat this pretty loosely.
On rare occasions--like SBC braking on W211 and maybe others--there is a warranty extension. That component is, for example, now warranted for 10 years, Mercedes having I imagine read the riot act to Bosch.
IMHO it's worth it for USA owners to periodially purchase the one-day ($18) subscription to Startekinfo to look for the latest DTBs--they are published fairly frequently. http://www.startekinfo.com
BTW, for R171 with M272 engines, the oil consumption, oil leak, and balancer shaft gear problems are all covered by DTB, so nice to get them done while still under warranty.
Note also, that "cosmetic" coverages go away when vehicle is converted to CPO warranty--so get your C-pillar sun-faded trim replaced in time.