This is a wonderful little gem of a place in a neighborhood filled with more conventional coffee/tea joints. For one thing, it's super-small and intimate, more like someone's living room, and there's only space for about eight people. The tables are small so don't think you can sprawl out your laptop and papers there. I'm not sure that there's wi-fi but, even if there is, this isn't the type of place to go web-surfing.
This is a cozy, European-style tea salon (not a cafe) for sampling high-grade teas and for having engaging conversations, either with your companion or with the outspoken, worldly and friendly owners.
Currently some of the baked goods (such as scones, muffins and cake) are vegan and efforts are underway to get them labeled so there's no confusion about what's what.
Make sure to sample some teas. You can get a pot (which consists of around 3 cups) for $3-5, depending on what tea you select. If you get a darker tea there's a good chance it'll make for a second steep, getting you double the tea for the same price. I find their Indian black teas to be exquisite but you can't go wrong with any of their multiple offerings.
Unlike its competitor TeaSource, La Société du Thé treats tea as an experience to be savored and understood, rather than a bulk commodity to be bought and sold. This place is an elegant anachronism in an age of to-go cups and standardized tea-bag offerings. I highly recommend it.