need ultraportable to replace my T61: x120e, x201, or Edge E220s?

My 2.5 yr old T61 still works fairly well, but I'm starting a job that will require a lot of commuting on public transit (and walking), so I need to get something significantly lighter. I know that I need to step down a bit in features/connectivity to get the lighter weight, but I'm not sure which of the current/upcoming Thinkpad lineup will be the best for me.

I'd like to spend less than $1000, but could spend up to $1500 for a good reason. I'd also like to get the laptop as soon as I can, but I'm willing to wait for the newer products to get the right system.

I will be using the laptop for word processing, surfing, and multimedia-heavy presentations (a VGA-out port would be very nice, which is a problem for the x120e, but I think I can get an adaptor for around $100, and hopefully soonish more places will have HDMI connectivity). No gaming.

My priorities, approximately in order:

portability/weight
stability/build quality
screen size - I'd like a slightly larger one if it's not going to add too much weight
longevity -- I usually can only afford a new computer every 3-4 years, so I'd prefer something that won't be obsolete immediately

I really want to get a Thinkpad, since the T61 is my third, but I don't know that much about the current lineup. I'd really appreciate advice, although I know that a lot of information about the new product line is speculation.

Thanks.

 

You can get the t410s, but it's a little pricey. Also moving from 14 to 12 inch screen is huge. Personally I could not be productive with anything smaller than 13."

 

The x120e has a VGA port, it's on the back. (IMO the processor isn't strong enough. It has enough juice for now, but in a few years may not be powerful enough depending on software demands.)