Is the word "data" now considered singular? If so, what about "datum"?

There are two conflicting usages. For example, a Google search for "the data suggest" returns 10,000,000 results, but a search for "the data suggests" still returns almost 2,000,000 hits.

Wiktionary says:

data uncountable or plural noun
1. Plural form of datum: pieces of information.
2. (uncountable, collectively) information.
3. A collection of object-units that are distinct from one another.

Usage notes

This word is more often used as an uncountable noun with a singular verb than as a plural noun, with singular datum.

Merriam-Webster says:

Definition

1: factual information (as measurements or statistics) used as a basis for reasoning, discussion, or calculation <the data is plentiful and easily available — H. A. Gleason, Jr.> <comprehensive data on economic growth have been published — N. H. Jacoby>

[...]

Usage Discussion

Data leads a life of its own quite independent of datum, of which it was originally the plural. It occurs in two constructions: as a plural noun (like earnings), taking a plural verb and plural modifiers (as these, many, a few) but not cardinal numbers, and serving as a referent for plural pronouns; and as an abstract mass noun (like information), taking a singular verb and singular modifiers (as this, much, little), and being referred to by a singular pronoun. Both constructions are standard. The plural construction is more common in print, perhaps because the house style of some publishers mandates it.

Emphasis mine.

As others have said, "data" is often used these days as an uncountable noun, either in the singular or plural. However, it is still also used as the plural of "datum". This answer is just to show that "datum" is also still a part of English, provoked by another answer that strangely claims that it isn't. (Too long for a comment.)

Looking through Google News gives, from recent news results:

• Pittsburgh Post-Gazette (US), October 2:

The most interesting datum to me in the National Journal/Pew poll is…

• Scienceblogs (Pharyngula) (US), October 1:

…a superficial news item about one datum.

• The Telegraph (UK), September 30 (reported speech):

"… with a single datum, you can’t say anything about…"

• The Economic Times (India), September 28:

…going to define the datum from which Mahindra…

• National Review Online (US), September 27:

God defend us from a man of one datum, particularly if that man is an economist, and particularly if the datum is wrong.

• NBC Washington, (US) September 24 [actually quoting The New York Times (US), August 19]:

…a capacious but intricately ordered narrative that in its majestic sweep seems to gather up every fresh datum of our shared millennial life.

• Columbia Journal Review (US), September 21:

Of course, as the authors of the article are quick to point out, a crucial datum is missing: the percentage of all published fiction written by men versus women.

• Harvard Crimson (US), September 21:

Researchers in some labs are irresponsibly subjective in their analyses: any turn of the head is counted as a positive datum.

All these (and many more; I got tired) in a span of two weeks. Among these publications are national and local newspapers, student magazines, and blogs. There also appear to exist standard phrases like "poverty datum line" and "chart datum level" (of rivers). Of course, there are also plenty of occurrences in the classical literature. (It occurs several times in the Sherlock Holmes canon I read as a child. :-))

Sure, "datum" not the most common of words, but claims that it's not a part of modern English, or that you need to wear a toga to use it, seem unjustified.

"Datum" is an irrelevant, because it is simply not true in modern English that 'datum' is the singular of 'data': even those who use 'data' as plural do not refer to one of the individual pieces of data as a datum.

Edited: Apparently I was wrong in this. I do not recall ever having met the usage, so I was generalising inadvisedly. Sorry.

I have always used 'data' as a mass noun, so said 'the data is'. I am aware that many (most?) academic publishers insist on 'the data are'.

From the NOAD:

data /ˈdædə/ /ˈdeɪdə/
noun [treated as sing. or pl.]
facts and statistics collected together for reference or analysis. See also datum.
• Computing the quantities, characters, or symbols on which operations are performed by a computer, being stored and transmitted in the form of electrical signals and recorded on magnetic, optical, or mechanical recording media.
• Philosophy things known or assumed as facts, making the basis of reasoning or calculation.

USAGE Data was originally the plural of the Latin word datum, something (e.g., a piece of information) given. _Data_ is now used as a singular where it means information : this data was prepared for the conference. It is used as a plural in technical contexts and when the collection of bits of information is stressed: all recent data on hurricanes are being compared. Avoid datas and datae, which are false plurals, neither English nor Latin.