If you are interested in picking up .pros Snapnames is the place to go. You can still pick up bargains. If you see a .pro somebody has already bid on, bid on it, the first bidder will win it automatically at $59 even if nobody bids during the auction so you are under no obligation to buy, but being in the auction will give you a feel for the price .pros sell at auction for. Also by cross checking the winning user name to the WHOIS after the drop, you can see which .pro domainer bought what and the value people attach to different types of keyword.
I picked up Truck.pro at Snapnames for $59 a couple of weeks ago, the .com sold for $101,000. The auction ended at $350 in August 09 but the buyer didn't pay, I emailed Snapnames 2-3 months after because I was the second highest bidder and the only bidder who had bid more than the start bid. They offer me the domain and I said I would take it if I paid the amount I would have won it at if it hadn't been for the bidder who didn't pay. Truck and Pro have a nice fit, if you do a Google search for Truck Pro you will see what I mean.
People will say but if Truck.pro sells for $59, that doesn't bode well for the extension. But the truth is only a very small % of domainers can register .pro, know about .pro, or have the time and inclination to monitor drops.
For example, when Lorry.com dropped a couple of months ago, 71 people bid for it on Snapnames, including me, Lorry is the UK word for Truck for anybody who doesn't know. It sold for about $10,000, if I had more money at the time, I would have bought it. You can't say Truck.com isn't worth $100,000+ because Lorry.com only sold for $10,000 or that any premium .com isn't worth $5m because Lorry.com only sold for $10,000 and so on. Snapnames offers a genuine opportunity to pick up domains for significantly less than their market value because people are looking for bargains and not everybody is tracking what is dropping so the auction is full of enthusiasts and resellers on very low budgets looking for value.
The other place to look for .pro bargains is Encirca. They show what is dropping on Encirca.com/feed This used to be the place to go because at one point 95% of the 6,500 .pros regged were held with Encirca so anything decent that dropped was on their Expiring list. When I started regging .pros, there was a period when .pros would drop at a few seconds after 8:57AM UK time so I was always at my PC before work manually hammering the WHOIS. You can't do this now, the drop times varies, and the premium keywords go to Snapnames. I think some people still pick up .pros this way. I bought Airplane.pro for $485 to add to my collection of "big rig" .pros like Yacht.pro, Boat.pro, and Truck.pro, I'm pretty sure the seller picked it up on the drop the day before he sold it to me so I should have been paying more attention.
Sometimes just being known for buying .pros helps. When .pros cost $99 to renew, alot of premium keywords got dropped and sometimes people would offer me them to me at firesale prices a couple of days before. For example, I picked up Salon.pro and London.pro for very modest sums this way. Salon.pro is the type of .pro I really go for. There is a very strong association between Salon and Professional or Pro. Salon products are advertised as professional to convince women to pay 5 times as much as they need to pay in a supermarket for a similar product. Salon is also a professional context keyword, skilled hairdressers and therapists work in a salon. I think keywords like this work well in .pro, I bought Studio.pro and Office.pro on the aftermarket based on this logic. If you look on dnsaleprice, the keywords that sell for the most money tend to have a professional context or link, for example Freelance.pro sold for $5,440 in Oct 08 and Chef.pro sold for $3,650 in May 08. I kicked myself when Chef.pro sold, I could have bought it for about $600 the year before.