Sorry couldn't resist... may the thread die after this message

Steve,
I agree kinda. But don't you have to standardize on something? You standardize but enable enough flexibility to deviate only when necessary.
It is like the English language. We have a baseline for the language. New words and meanings are added as the human race matures. Old words take on new meanings as well. The word Gay in 1950s meant happy. Today however it means something totally different. But the way it is spelled and pronounced is the same. We also have some spanish, latin, french, and other languages mized in with the etomology of english but that does not mean we begin integrating with the english language pure spanish per se. We do not want Spanglish but English.
Same with UML. UML is a visual communications language and therefore will mature over time. Adopt 1.1, when 1.2 comes out adopt it in full..1.3, 1.4 etc. While there may be some changes, in the meanings of the notation, the notation stays the same. It is the capturing of the change in the meaning that is paramount.
Rusty
Welll... come on though, English language is defined by its usage, not some arbitrary standard, albeit over a time scale that is a lot slower than other standards (but then, UML would change a lot more slowly if 2 billion people in the world used it every waking moment of their lives

Even grammar changes. The nounizing of verbs and verbizing of nouns are much more common in recent years to what it was. 'Yous' as plural for second person plural is increasingly common across the world. New words and vocabulary evolve even more rapidly with the internet. In other words, people run with it. Even 5 years ago, would you have had any idea what i meant by 'blog', 'spam', 'to text someone', etc etc sure I think you get my point.
Speaking of Spanglish, it's what's becoming increasingly common in Spanish. For instance there are two words for 'link' in Spanish: 'enlace' or 'vínculo' but here in Spain people just use 'link' as they do 'training', 'marketing', 'scope' etc. (A funny side is that people pronounce foreign brand names with a literal Spanish accent... like 'Oracle' for instance is pronounced 'orAH-kleh' and there was a time when I had absolutely -no- idea what they were saying until they wrote it down
New words are more often than not directly transplanted into other languages. It happened in English too, there are bundles of foreign words and concepts.
So I'm not so sure it's as clear-cut as that. I think it's ok to use these tools
to communicate the intent of the design. You're not going to do sequence diagrams for every flow, only for core use cases for analysis (with Together actually, I've used the sequence diagram from code option to understand the method call stack, very powerful analysis tool).
My €0.02