Better Battery
Standard SSD
802.11ac
Yes, Siri
More than one input for headphones/speakers
Better sound system (like the anniversary Mac)
Maybe a 17" Retina with a number pad on the keyboard =)?
Whatever the new 13" Retina MacBook Pro offers, it cannot come soon enough. The existing 13" MacBook Pro is too heavy to lug around airports on a regular basis while the MacBook Air simply doesn't have the power or screen quality to match the rMBP 15" model that power users need.
I would like to see 1 TB SSD offered and I just don't care what it costs.

The 17" is dead.
13" MBPr with a dedicated GPU. Hopefully we get that this year.
Between iCloud, 802.11n and Thunderbolt/USB3 that's not a problem for me anymore. If I need more fast disk space I can attach an external TB or USB3 SSD drive. Otherwise attaching to something like the Seagate GoFlex Satellite should be good enough since that feeds my iPads as well. Even less of an issue when we get 802.11ac across all the products.
Mostly 256GB is plenty for OS, base apps and normal files. It's my pictures, movies, virtual machines that chew up vast amounts of disk space.
The 13" MBA + GoFlex Satellite + iPad combo is still smaller than most alternative travel combos. And I can connect the Satellite via USB3.
That said my "optimal" machine would be a 13" MBPr with 1GB 650M, 256GB SSD, 8GB RAM and a quad i7 for $1799.
That's probably too much to ask. Dual i7. :)
A bit bigger than the MBA but powerful enough to be a desktop replacement when attached to a 27" display.
Time for an upgrade!
The internet also gives voice to every idiot that ever walked the earth. You need to take these reports with a grain of salt. More so you need to consider that Apple sells millions of these and as such things will get past quality control of damaged in transit. The good thing is that Apple stands behind the product.
About the only thing I see here that has any validity is the issue with the screen. Even that is overblown by people that can't be satisfied. Think about it somebody returned a retina MBP 5 times, it would seem that the odds of getting that many bad laptops in a row is pretty extreme.

Figuring out the optimal time to upgrade is tough. The old adage of buy when you need it makes good sense and then let the chips fall were they may. Right now I'm letting economics dictate my not purchasing a new Mac. That may mean Haswell will be here before I'm ready to buy or my MBP could give up the ghost (it has taken a beating). Look at it this way though, next year just means a new model with new problems. You really never get away from the issues of new product glitches.
Maybe. This computer has held up extremely well. I replaced the hard drive with an SSD a few years ago. I had the battery replaced awhile back because I got it to 1,000 charge cycles and it started failing. It's just that at some point I'd like to be able to do the AirPlay mirroring to an Apple TV, I'm also annoyed the Mini Displayport on this model doesn't output sound so hooking up to a HDTV is a pain without the extra audio cable. Part of me wants to wait to see what comes with the 13-inch retina MacBook Pro if I'm forced to downsize.... I'm also a little leery about getting a computer that I can't easily upgrade especially since it's $2,000. I don't think I'd be as leery if the thing wasn't so expensive.
By definition, no, it isn't overpriced.
There are a number of expensive notebooks on the market. The macbook pros are the only ones that come to mind that could truly be considered mass market items, but others do exist. Grabbing the $1800 versions on refurb doesn't work out that bad if you're trying to save cash on it. Macs have always carried a high cost of entry. They've just never fallen below certain price barriers.


Improved battery life - plenty of laptops get 10+ hours. Just get a business laptop from Lenovo, HP, or Dell - all offer larger standard batteries, and if you use a slice battery as well you can get 20-30 hours of battery life.
Voice recognition - currently available laptop microphones are perfectly up to the task. Apple just needs to actually offer the software.
It's not overpriced. It's specs are around the same as 2000$ notebooks from HP, Lenovo, Dell, Sony, etc...
A fully pimped out Lenovo ThinkPad W530 will run you close to $3000... Panasonic Toughbooks can go past $4000. I personally bought a Thinkpad for $1700.
While I wouldn't call the MBP Retina cheap, it's actually fairly good value when compared to the competition. People need to compare the proverbial Apples to Apples - and not simply assume that every Apple product is trying to be the iPhone, iPad, or MacBook Air...