Strengths versus Other

Focus on risk- and value-driven priorities.
Emphasizes building a cohesive architecture early, preferring existing components.
Evolutionary and incremental requirements and development, and adaptive behavior.
Well-defined workproducts, offering a common vocabulary.
The guidelines and best practices are a good foundation.
Offers guidance on many disciplines, from requirements to configuration management.
Easily combined with techniques from other methods.
Easily customized; encourages minimal "light" versions.
RUP product has easily accessible useful advice, and standard project templates.
Proven to scale to large or small projects.
Encourages use cases where appropriate.
Widely adopted; hence, learning and consulting resources.
Created with many customers, refined on many projects; not a speculative process.

^[3] Could be viewed as a weakness, strength, or deliberate desirable exclusion depending on point of view.

Many details.
UP phases are often incorrectly applied in a waterfall style.
Minimal attention to the social dynamics and communication aspects of successful and sustainable development practices. Contrast to Scrum and XP.
The RUP product can give the (unintended) impression of promoting a very defined and predictable development process, as though software was mass manufacturing rather than new product development.