I thought the nikkor lenses are expensive
NOT true! Please post your source of this information.
The truth is, prices of Nikon and Canon lenses are within 10% of each other, with both sides having some lenses cheaper than the other and costlier than the other. If you are saying otherwise, please post some comparisons to support your claim.
canon has better 3rd party lens compatibility compared to nikon.
Again, NOT true. Sigma, the most prolific lens maker after Nikon and Canon, and undoubtedly the top 3rd party manufacturer, has known issues with Canon bodies.
Also many reviews online say that canon is much better as a photo + video camera.
Yes, the sites that are sponsored by Canon say so blatantly. As a company Canon has become a consumer company, which wants to sell it's products to "spec-sheet" readers. No wonder Canon has been pushing up the mega-pixels all the time, whereas other manufacturers realized that there were more than mega-pixels to photography. They went ahead with real R&D, whereas Canon remained busy pushing up the mega-pixel count.
The review sites you mention are "mega-pixel" friendly sites, and they have a certain section of the market on their target (read unsuspecting consumers). The real photographers who care about image quality (not megapixel, not video) go for Nikon.