TLDR:
v2.10.1 released on Nov 21st with an abundance of fixes.
v2.10.2 released on Nov 26th
v2.10.3 released on Dec 4th
v2.10.4 released on Dec 18th

We'll resume normal development (perf improvements, PR reviews, new features, etc) near the end of this week once the remaining v2.10 issues have been fixed 🚀

We've had lots of issues with url compatibility between v2.9.2 and v2.10.X, and are working to resolve these promptly.

These might be addressed, but aren't currently attached to a patch release:

• mypy type-checking issues affecting a Field's default value or default_factory after upgrade to 2.10 #10950
• Regression using regex_engine python-re in pydantic >= 2.10b1 #11042

For v2.10.4

• Date field with year zero will raise ValueError instead of ValidationError #10967
  • Fix ValueError on year zero pydantic-core#1583
• v2.10.x: Raises TypeError: mro() returned a non-class ('PydanticRecursiveRef') #11024
  • Make sure the type reference is removed from the seen references #11143
• Pydantic 2.10.x not installable from Azure devops due to description size #11071
  • Fix package description limit bound #11140
• pydantic.errors.PydanticUndefinedAnnotation: name 'T' is not defined when using from __future__ import annotations with a genetic function #11076 and validate_call cannot handle parameters annotated with None #11073
  • Properly fetch PEP 695 type params for functions, do not fetch annotations from signature #11093
• Comparison between AnyUrl objects is not working #11069
  • Fix for comparison of AnyUrl objects #11082
• AnyUrl: TypeError: object of type 'AnyUrl' has no len() #11092
  • Add len to _BaseUrl to avoid TypeError #11111
• Include JSON Schema input core schema in function schemas #11085
  • JSON Schema gen chokes on BeforeValidator with a union in the json_schema_input_type #11033

For v2.10.3

• Data class with defer_build set to true causes the error AttributeError: type object '...' has no attribute '__pydantic_fields__'. Did you mean: '__pydantic_config__' #10953
  • Set fields when defer_build is set on Pydantic dataclasses #10984
• Problem generating OpenAPI schema for models with an enum as the key of a dict #10960
  • Do not resolve the JSON Schema reference for dict core schema keys #10989
• Model is not fully defined together with from __future__ import annotations (Started in version 2.10.0) #11004
  • Use the globals of the function when evaluating the return type for PlainSerializer and WrapSerializer functions #11008
• 2.10: mypy (with pydantic.mypy) complains about Too few arguments on default factory  #10945
  • Add a default_factory_takes_validated_data property to FieldInfo #11034

URL issues, @sydney-runkle is working on these

• In 2.10.x AnyUrl does not validate data uris #10968
  • Fix host required enforcement for urls to be compatible with v2.9 behavior #11027
• Can't override constraints with annotations in version 2.10 #11007
  • Fix host required enforcement for urls to be compatible with v2.9 behavior #11027
• v2.10.x: OpenAPI schema generation omits constraints for HttpUrl #11019
  • Fix url json schema in serialization mode #11035

For 2.10.2:

• Missing eval-type-backport as required dependency in 2.10.* Pydantic line for Python 3.8/3.9 #10958
  • Do not evaluate annotations for private fields #10962
• V2.10.1 custom model_serializer causes problems with dumping model to json #10965
  • Support serialization as any for Secret types and Url types #10947
• 2.10: Trouble serializing url types (as any), similar to secret types #10946
  • Support serialization as any for Secret types and Url types #10947
• Type of "Field" is partially unknown after v2.10 #10971
  • Fix type hint of Field.default to be compatible with Python 3.8 and 3.9 #10972
• In 2.10.1 the AnyHttpUrl is not hashable any more #10955
  • hashing support for urls #10975
• Signature of "__replace__" incompatible - RootModel #10970
  • Hide BaseModel.__replace__ definition from type checkers #10979

Handled in 2.10.1:

• 2.10: validated_data must be provided if call_default_factory is True (affets: SQLModel) #10912
  • Relax check for validated data in default factory utils #10909
• 2.10: dataclass config issues (arbitrary_types_allowed, aliases, etc) #10917
  • Use the parent configuration during schema generation for stdlib dataclasses #10928
• 2.10: Issue with forward annotations and serializers/computed_field (raises: <model> is not fully defined) #10919
  • Use the globals of the function when evaluating the return type of serializers and computed_fields #10929
• 2.10: Type checking error on model_fields and model_computed_fields with mypy #10907
  • Fix type checking issue with model_fields and model_computed_fields #10911
• 2.10: URL types issues (application of constraints) #10914
  • Fix url constraint application #10922
• 2.10: custom complex serialization behavior changed? #10926
  • Fix serialization inference for complex types in python pydantic-core#1549
• 2.10: HttpUrl equality behaves differently when using model_validate vs model constructor #10932
  • Fix URL equality with different validation methods #10934
• 2.10: Blank model title no longer respected by generated JSON schema #10935
  • Fix JSON schema title when specified as '' #10936

Questions:

• 2.10: AnyHttpUrl is no longer subclass of pydantic_core.Url (according to mypy) #10920
• pydantic.networks.KafkaDsn type prohibits a valid bootstrap.servers values #10996
• 2.10: question about needing model rebuild with circular types #10925
• PostgresDsn does not accept correct postgresql:///dbname since 2.10, was accepted before #11023
• 'Url' type casts left around when serializing model to a dictionary #10998
• Numpy array alias as type regression between 2.9.2 and 2.10.0 (and later) #11000