For highly sought after keywords like "lesbian" or "milf", here's how the domain extensions compare:
.XXX:
- Most recognized adult-specific TLD with longer market presence
- More established reputation in the adult industry
- Some SEO professionals note it may be easier for ISPs to block
- Has more brand recognition with users
.PORN:
- Clearly identifies content type
- Less established than .XXX but very direct
- More recent addition to adult TLDs
.SEX:
- Broader appeal and less explicit than .PORN
- May attract different search intent (educational vs. entertainment)
- Potentially less likely to be automatically filtered
For high-value keywords, .XXX appears to have the edge in terms of industry recognition and established presence, though each has pros and cons. Many adult site operators actually maintain multiple domain extensions (particularly keeping a .COM alongside specialized extensions) to maximize visibility and avoid potential filtering issues.
The effectiveness ultimately depends on your specific SEO strategy, target audience, and whether you're more concerned about direct navigation or search engine visibility