Few ownership groups around NA can compare to MLSE. What might be a losing proposition in most cities, due to market size, corporate base, leases to 3rd party arenas, ability to redeploy or pool resources with other teams under the same group, etc...
MLSE owns the arena, so while the WNBA team will pay rent, it can be made to be favorable (pr at least flexible). Further, with operations in 4 sports leagues already, the ability to put experienced company people on the job is going to be better than many other places... and the market here is hot for basketball right now.
But they may also feel like Toronto is special in some way, which it is. Recall when TFC jpijed MLS, another league that had gone through growing paind and instability... TFC joins the league and within the year, they become the envy of the league in terms of fan support and game experience and league wide supports grows as other fanbases up their games. MLS expansion to Toronto was a really big stepping stone for the league as a whole, and MLS was willing to foot the bill and ride out the first few years until profitability and success followed.
I have little doubt that they will lean heavily on the TFC and 905 experience - both teams winning a championship - and feel they can leverage that along with the Raptors success and make it happen in the WNBA also.
Buy they have to play at either Scotiabank Arena or at Coca Cola Place (former Ricoh at the CNE). Putting the team in Mississauga (or Hamilton or KW as someone suggested) ensutes they are forever viewed as a minor league thing and will not hit the potential peak that they could if being a fully legit "Toronto" team. It needs to be packaged as a first tier, major level product or it isn't worth doing at all.
As for a name... Huskies will likely rise to the top of the list, but other names from the Raptors naming contest could also come back, like the Towers or Beavers (giggity).