For me, both data and information are singular and take singular verbs. I correct, e.g., the phrase "the data have been updated" if I come across it. Originally of course, data was plural, but that has been transformed over time. Information doesn't have this ambiguity (außer vom Deutschen herkommend: "Diese Informationen sind ...")

"data" and "information" are singular for me too.
But "data" is definitely also fairly commonly used with a plural verb.

No -- "information" and data do not have to be treated in the same way! Not at all.

Agree with Ghol with the exception that I use data as plural. I certainly don't think you can call either singular or plural usage wrong though, Nancy. Information can obviously be made plural, as can other singular-only words, by using a suitable addition (pieces of information, items of news, etc.).

Perhaps concerning data this is another AE / BE difference, i.e. AE has left the plural behind, but BE still uses it sometimes?

Thanks for your comments. To bad I'm always hoping languages were more predictable and orderly ;-) Coming to think of it, I hated Latin, which is more structured and predictable then Englisch.
The translator I worked with was british, which suppports that it may be an AE/BE difference in the usage of data+plural/singular.

@CJ, I'm not sure... My colleague (BE) uses data with a singular verb...

>>To bad I'm always hoping languages were more predictable and orderly.

Aber es ist doch vollkommen folgerichtig. Data kommt aus dem Lateinischen und ist der Plural von Datum.

If I am talking with (or writing to) academic colleagues, I'll use data with a plural verb, since that is technically correct. But in ordinary conversation that sounds too stuffy these days, so I'll use the singular. But as a trained researcher, I was socialized to see "data" as plural!

Once again, my thoughts are congruent with Miss G's, point for point.

The American Heritage Dict. has a long usage note about this point:
http://www.bartleby.com/61/51/D0035100.html

and Garner's Dict. of Mod. American Usage has a column and a half about it, which generally follows Miss G's and the usage notes above. Select excerpts that offer something new:
"In one particular context, though, data is rarely treated as a singular: when it begins a clause and is not precede by the definite article. E.g. 'Data over the lst two years suggest that the rate at which gay men get AIDS has finally begun to falten out.
_Datum_, the 'true' singular, is still sometimes used when a single piece of information is referred to..." with more examples following. And again:

"Because _data_ can be either a count noun or a mass noun, both _many_ data and _much_ data are correct..." again with examples.

Garner refers to 'data' as a SKUNKED TERM, saying "As a historian of the English language once put it, 'A student with one year of Latin [knows] that _data_ and _phenomena_ are plural.' And that's what makes the term skunked: few people use it as a plural, yet many know that it techinically is a plural. Whatever you do, if you use data in a context in which its number becomes known, you'll bother some of your readers. Perhaps 50 years from now--maybe sooner, maybe later--the term will no longer be skunked: eerybody will accept it as a collective. But not yet."

These are only the highlights, he has more to say. I recommend this usage book to anyone interested in the fine points of usage.

Wir benutzen data im Plural, information hingegen im Singular.
Im Zweifelsfall halten wir uns in unserer Anwaltskanzlei (Intellectual Property Law) an Garner, A Dictionary of Modern Legal Usage, worin es zu "data" heisst: Technically the plural of datum, has, since the 1940s been increasingly often thought of as a mass noun taking a singular verb. But in formal contexts it is preferably treated as a plural - e.g.: "If the new data do not fit, ... must be modified to accommodate them".
...
The Oxfored Guide allows the singular use of data in computing and allied disciplines; whether lawyers own computers or not, they should use data as a plural.
In one particular context, though, data is invariably treated as a plural: when it begins a clause and is not preceded by the definite article. E.g., "data over the last two years suggest that ...

I just happened to use 'data' in a reply to topic Mehrjahresvergleich http://www.leo.org/cgi-bin/dict/forum/forum.c... as a plural. It would have sounded funny to me to have used a singular verb in that sentence, but perhaps that's just my bias.

jet: looks like we each have usage guides from the same series...

What got me confused was the different handeling of data and information. But, as some of you pointed out, my perception that they are both mass nouns was incorrect.
Information is a mass noun and therefore requires the singular, data is basicly the plural form of datum and though it is in the process of being transformed into a mass noun, gramatically speaking it still requires the plural verb.

Thanks you all for your input.