Ruby On Rails Deprecations

These things have all been deprecated. Some of them may not exist at all in
Rails 2.0. You've been warned!

@params
Use params[] instead.
@session
Use session[] instead.
@flash
Use flash[] instead.
@request
Use request[] instead.
@env
Use env[] instead.
find_all
Use find(:all) instead.
find_first
Use find(:first) instead.
render_partial
Use render :partial instead.
push_with_attributes
Use has_many :through instead.
Object#type
Use Object#class instead.
content_for_layout
Use yield instead.
content_for_some_fragment
Use yield :some_fragment instead.

These things are not technically deprecated, but stay away.
components
Use of components are frowned upon.
paginate :model
The default paginator is slow. Writing your own may be faster.