We've only been in a couple of times but so far it has been nothing shy of fantastic. Very knowledgeable, and more importantly to me very friendly staff that seems to have found the right balance of helping out without being overbearing. It seems like the vast majority of the wines are in the $12-20 range, and everything we've picked up so far has been great.
The small placards that give ratings for each wine (a sliding scale - very easy to interpret and very helpful) can help you pick a wine based on actual information rather than a price point/label/look/6th sense(?)/hunch/etc. Like something full bodied and dry? You'll find what you are looking for, and odds are Mark and Laura will help you. They also have their picks of the week.
We've yet to participate in a tasting, but visited last night during one (complete with cheeses and chocolates to compliment the tasting it appeared) but it is something we plan on doing in the near future. While shopping around they even gave us a tasting of a red and white, both were great.
The selection and presentation are top notch, but ultimately how friendly Mark and Laura have been will keep us coming back.