tuittu, what do you mean? You actually have the choice to point to a specific version, or the latest version. See here for more details.
The versioning system allows your application to specify a desired version with as much precision as it needs. By dropping version fields, you end up wild carding a field. For instance, consider a set of versions:
1.9.1
1.8.4
1.8.2
Specifying a version of “1.8.2” will select the obvious version. This is because a fully specified version was used. Specifying a version of “1.8” would select version 1.8.4 since this is the highest versioned release in the 1.8 branch. For much the same reason, a request for “1” will end up loading version 1.9.1. Note, these versioning semantics work the same way when using google.load and when using direct script urls.