The N900 runs Maemo 5, also called Fremantle. http://maemo.org/packages/view/tear/ As you can see here, apparently so. But it appears that the port is not headed up by Bundyo but by Qwerty12, to whom I'm already indebted for some Tear development (specifically, Find on Page; probably other stuff, too).
OTOH, I've heard such good stuff about the N900 browser, I don't see the point of porting Tear to Fremantle. We desperately needed it on the N8x0's since it's so much faster. I can't imagine tolerating my N800 without it. But it has various lacunae, like no Save function, trouble with opening .deb files, problems with highlighting that make it, for example, impossible to highlight a part of a post on this forum and hit the Link icon or the Bold icon to impact what you've highlighted, etc. I haven't used the N900 browser, but if it's all that it's cracked up to be, why have Tear for it, too?