Its because WRPGs are BETTER now.  It used to be they were different but that ship has sailed.  Now they are just flat out better.  Games from Bioware are the best RPGs available and have been for years, followed closely by Bethesda and sometimes Obsidian (who picks up Bioware's leftovers).  There just aren't any JRPGs from the last 5 years that compete at ALL with games like Fallout 3, Oblivion, the Witcher, Jade Empire, KOTOR ect ect ect.  Grind and stats just don't do it any more.  What makes WRPGs great is the addition of CHOICE.  branching character options, multiple dialogue options, moral choice and repercussions...every game I listed has those things and it is a huge boon.  Once you've played KOTOR and games that adopted the light/dark morality dynamic its so hard to go to preset canned dialogue and stories without any real branching choice.  

   In a game like Eternal Sonata, which I DO like, everything is set and you just follow a path leveling up your character in a pretty set way.  In Fallout 3 you arrive at a new town and can either help the sheriff out or take a 500 cap payout from a sleezy character and nuke the town.  JRPGs really need to evolve into something more then grind and repetition of what made FF1 a hit in 1988.  You'd think over 20 years they would be able to make something better consistently.

   I do LIKE JRPGs but I hold no illusions about them being the best thing out there these days.  WRPGs are just so good thanks largely to Bioware and Dungeons and Dragons games like Baldurs gate as a trailblazer its really hard to justify JRPGs as anything near the best out there.

That's a ridiculous statement.  First of all, Pokemon has outsold every WRPG this gen.  Almost combined. It also outsold WoW.  Signifficantly. It also sold far more than the Pokemon games last gen, showing a strengthening of that franchise in the genre.  There are also far more million selling JRPGs this gen than WRPGs counting handhelds, and no JRPG franchise or genre has sold less this gen than it did last gen.  There is an even larger difference between million selling JRPGs and million selling MMORPGs, of which there is only one with more than a million players right now. 

Your ignorance is showing.  You might want to cover that up.

Pokemon did outsell every WRPG this gen, but the other jRPGs didn't follow Pokemon. There are considerably more wRPGs coming out than jRPGs - the strength is in numbers. jRPGs have handhelds under wraps, but wRPGs have PC and Consoles.

As for MMORPGs. don't delude yourself, MMOs are machines. Do you know how many total subscribers Lineage 2 had? Over 14 millions. Not bad for a MMORPG with only a tenth of WoW's success. Everquest, which peaked at 500k active subscribers, sold 3.5 millions copies.
There are dozens of millions of gamers playing mmos every month, and will get bigger with the boom in continental Asia and more MMO acceptance in the west. Also go check gamerankings and you'll notice the vast amount of mmos coming out compraed to jrpgs and wrpgs.

   Try the PC version, its VASTLY superior.  All the problems caused by the 360s inadequate hardware are solved and the game looks glorious.  Yes there were some limitations on end game explorations, but I never really had a problem since I tended to go to new places the second they were available and wait on continuing the main quest.  

   As to Mass Effect being over rated, if you're talking about the PC version that is 100% untrue.  The PC version of Mass Effect is the best RPG I've played since....well Bioshocks LAST great RPG, Jade Empire.  I'm sure it will be the best RPG out there until Dragon Age comes out, which will hold the crown until Mass Effect 2.  The only game to really give Bioshock a run for its WRPG money is probably the Witcher, which was flat out awesome (if you haven't played it go get the extended version now!!! It is just so very very awesome).

First of all, there are absolutely not more WRPGs than JRPGs in development.  In fact, the difference is well over 2 to 1 in JRPG favor. It's foolish to look to gamerankings for JRPGs releasing because A) They screw up on the genres (often completely missing SRPGs among the JRPGs), and B) They only record those being released in America, which the majority of JRPGs are not.

Second, MMOs are notorious for reporting trial accounts in their subscribers.  Even Blizzard does it.  They consider that an "active subscription."  Also, lineage never topped 3 million active subscribers.  But again, this is all besides the point:  You said popularity.  You said that WRPGs and MMORPGs are becomming more popular, but this simply is not true.  MMORPGs make more money (well the ones that don't flop anyway, and when an MMO flops its a massive flop), but they are not the better selling genre.  You have to dig all the way back to a 1998 MMORPG to find one besides WoW which even remotely competed in sales.

Famitsu has rated The Last Remnant with a 38/40 score. But Famitsu seems to rate almost every Square Enix rpg very high.

You're joking, right?  OXM gives the game a 7/10 yet TLR gets the best scores of any 360 JRPG in Famitsu.  Famitsu better be giving SOTLH atleast a 36/40 if TLR gets a 38/40.  BTW, I read somewhere that Famitsu actually gave TLR a 34/40.