The surging interest in the metaverse reflects a broader shift toward more immersive and interactive forms of digital platforms. Given the complex and multifaceted nature of these newly developing services, a systematic means to assess their technological dimensions, effectiveness, and impact is required. We thus present the status, direction, and challenges of establishing an evaluation framework for metaverse platforms. Based on a review of prior attempts to define and evaluate the metaverse, we propose our own definition of the metaverse-as-platform and derive six factors as a viable direction for metaverse platform evaluation. We address the challenges of developing these factors as a practical tool to assess, analyze, and shape the metaverse platform industry.