Vladimir Sizikov wrote:
> Also, what would happen with 1.8.6/1.8.7 lines, will they get the
> update, or will they continue to exhibit current behavior? You see,
> any incompatible changes quickly lead to  very messy situations. If
> somebody is relying on older behavior, they will get *silent* , hidden
> errors when upgrading.

That is why projects should use the RubyGems rational version 
numbering system [1], which clearly and loudly indicates to the user 
whether any incompatible changes are included in a release.  This 
"major.minor.patch" numbering policy is summarized as follows:

┌──────────────────────────┬─────┬─────┬─────┐
│Version number components:│Major│Minor│Patch│
├──────────────────────────┼─────┼─────┼─────┤
│  Backwards compatible?   │no   │yes  │yes  │
├──────────────────────────┼─────┼─────┼─────┤
│      New features?       │yes  │yes  │no   │
├──────────────────────────┼─────┼─────┼─────┤
│        Bug fixes?        │yes  │yes  │yes  │
└──────────────────────────┴─────┴─────┴─────┘

[1] http://www.rubygems.org/read/chapter/7