After having completed 'Diplomatic Immunity", I was unable to begin the next quest ("Cornered Rat") in the main storyline. I went to Brynjolf, did all the thieves guild quests to try to get him to take me to esbern, didnt work. Now im in charge of the thieves guild, and i still cant get anyone to bring me to Esbern. I tried to just go down to the warrens and talk to Esbern, but he doesnt open the door. Now I am a 36 Dark Elf Mage, and unable to progress any further in the main story line, and im stuck flopping around doing side missions. Any plans of fixing this in the patch? I've seen different console commands for PC users to just skip the quest entirely and move on to the next one, but as a PS3 user im screwed?

I am stuck at the same place, cant progress any further

Be aware that if you do manage to start 'A Cornered Rat' and you've previously been into The Karthspire caves and completed the two puzzles it'll also break the quest line (this is the quest after the 'Cornered Rat' called 'Alduin's Wall'. So I managed to get slightly further and due to me being a nosey sod and having been in the The Karthspire previously I'm now stuck....

I'm probably showing my age but I've been playing video games as far back as the Atari, SNES and Sega Megadrive and have NEVER had a game so poorly designed as this one (ok there may have been a couple of dodgy games on the Atari...however they were developed in someone's bedroom at minimal cost, NOT with a budget of millions and profits in the billions!!!)

It seems quite a few people have had this problem, me included. Unless it gets patched in 1.4 (unlikely) then you'll just have to start a new character.

It's just stupid really, you'd think Bethesda would at least make sure their main quest line shouldn't break. Apparently, that's beyond their capability.

Thats a misrepresentation. I'm from as far back as that and maybe more and I've seen plenty of busted games. Those games of old even when the industry in the 90's really started to ramp up (Wing commander, Strike commander, X-wing) Had pretty serious issues that unless you had BBS you could do nothing about. Those games were also simpler compared to what is being produced today. Most of which is not much of an evolution. Skyrim is ambiguous to say the least. Even when it was first being reported on, I had a funny feeling it would end up being problematic at first. Neverwinter nights when through exactly the same crap, anyone remember the bug with the brain thingy not even 5 minutes into the game? Took Bioware 6 weeks to fix it and in the end it was a user using the mod tools that properly scripted it and released it to the public. 5 mins into the game and a majority of the users could not advance. I dare say you could go into BioWare forum archives and read up to your hearts content on it.

You can talk to the barkeep as well and he will give you directions, actually I think any of the main thieves guild members can. You don't need them though to find Esbern. Just head in the Ratway warrens and as long as you have already gotten the password from Delphine in Riverwood you should be alright.