just a note from "the engineering department": Not every USB receptacle coming off is automatically a case for warranty. You can make the USB come off on virtually any arbitrary device, as well as e.g. break the LCD glass. For the glass it was a warranty case only if there's no obvious external force being applied. For the USB I'd guess it's a warranty case when the USB was poorly soldered which means the pads don't come off from PCB. If you applied so much bending force to the plug that the perfectly soldered USB receptacle rips off the copper pads from the PCB then very usually I'd refuse to accept this for a warranty case (unless PCB was notorious to have defective glue used to laminate the layers, which I never actually heard of for any device).
Nokia accepted USB warranty replacement on the rationale there were quite a number of poorly soldered devices where USB came off easily, brute force never is covered by any warranty though - usually (except for leatherman afaik).

/j

Today I have handed over my N900 to a Nokia care center and they accepted to repair it under warranty. But what they also mentioned is, there is 50% of chance that they may not be able to repair the N900. Being N900 is not in production anymore, they also wanted a choice of replacement from the options - E7 and N8. I have said that I would be more than happy to have my N900 repaired instead of a E7/N8 replacement. I have also said that if at all that cannot be repaired and I should accept a replacement, I will settle with any Linux device with a keyboard and 32GB build-in memory. They said they will look into it.

I am wondering what will I get done!!

probably not much but best thing you can do is take the e7, sell it and buy a n900 or two