Is it accepted and used by indexing platforms such as ISI, Scopus, etc?
Although the ORCID number is described in its website and in wikipedia, you may give insights on its current practical use, as well as its prospects and challenges.
In fact, ORCID is much more useful. It is worth noting that various publishers use different citations styles. Some require last names at the beginning, others first names or initials only.
ORCID helps to assign given reference to the right person.
All the good reference should have is DOI and ORCIDs of authors (although ORCIDs can also be retrieved from DOI databases). Everything else is just a decoration.
Indeed, while ORCID misses some publications it is perhaps still the best database for your work. I'm quite sure that it is also a very welcome site for those (like governmental agencies, or even your employers) who - for example - want to see what everyone in a given department is doing, have been doing over the years, and lately are doing. It's very easy to see the development, thanks to the simple statistics that you get.
Yes I also agree with Dr Artur, it has multiple use. You can use it in the article submission in few journals. Other journals are also thinking to use it.