With regards to CC quality certification –
COPC is good, it was developed with the Malcolm Baldridge Quality Award as a base; but tweaked keeping in mind customer facing (read CC) organisations. (However, it is extremely simplistic and has the documentation elements of an ISO)
Six Sigma is not a quality certification per-se; more of a quality standard —- extremely powerful when used in conjunction with a strong management team. (Go on the net and read about the following companies —- GE, Motorola and Allied Signals)
ISO — the template can be bought for 3-4 lakhs; its just a symbol you put on your letterhead.
CORE/CCS/Help Desk Certification et al are too insignificant to even consider.
However, dont believe the consultants who say that COPC / 6Sigma will get you business, because it wont. Plus, think about it this way —- no body can stop you from implementing COPC/6Sigma —- you dont need to be certified to improve people and processes.
Running is good for health, u dont need to pay for a marathon —- just run! (Bad example, but proves my point!)