Actually, this may surprise you, but viticulture has been relatively advanced for quite a long time. De Re Rustica is a fascinating read on Roman agricultural practices, and many, including the parts on viticulture, wouldn't seem out of place in much more contemporary manuals. The processes, both for cultivation as well as production, are largely familiar. The main difference between Roman and modern wines was likely their alcohol content, as both Greek and Roman wines likely had as high as 15% or 20% ABV, compared with 10-12% or so in most modern wines.

Consumption of wine was often very different as well. Mixing water with wine is a practice that is well attested in both Greek and Roman sources, as well as adding everything from spices to honey to increase flavour, and especially, add sweetness. Indeed, Romans were most fond of very sweet wine varieties.

What major technological advancements have effected the taste, smell and even bottling of wine?

Since you say classical I will draw the line at the late roman era and list changes in viticulture and enology from that time:

• Oak Barrels: The romans store their wine in clay amphoras before barrels started to become widespread in the early middle ages. New oak barrels impart fairly significant flavors such as char/smoke, vanilla and wood. The Amphoras were lined with pitch (burnt pine resin) so classical wines would have that flavor which were lacking in later wines.
• Destemmers: Most modern wine is made without the stems of the grape clusters being added to the fermentation vessel. Stems add flavors ranging from woody to vegetal to the finished wine. Only a small minority of modern wine has these flavors but all ancient wine would.
• S02: Almost all modern wine has potassium metabisulfite added to it add the time of fermentation and bottling to help protect it from spoilage and oxidation. Modern wine usually tastes "fresh and clean" but ancient wine comparison would like have a more nutty and oxidized "sherry-like" quality that would stand out to you.
• Bottles/Corks: This may surprise you but its only in the last 120 years or so that wine started being bottled by the winery. Before that time wine was shipped in amphora or barrel and then servered from those container directly to the drinkers. This has a few implications for how wine tasted. For one thing barrels or amphoras would sit half-empty for a while as wine was drawn for it over a period of time so the above mentioned oxidization aromas and flavors would be even more pronounced. Also, once combined with corks and so2, bottles allowed wine to be aged significantly longer than even before. These allowed wine to age without heavy oxidation and this aging created new flavors and aromas. Harsh tannins are transformed making the wine softer and more elegant and fruit flavors go through a chemical process called esterification that produces complex and unique flavors and aromas.

How similar in taste would ancient wine be compared with the vast amount of wines we have today?

As we have just seen certain winemaking processes between then and now have contributed to wine character differences but wines would also taste different because the Romans often added a lot of additives to their wines that we do not. The list of possible additives you might encounter:

• Fresh Water
• Salt Water
• Herbs
• Spices
• Lead (for sweetening)
• Honey
• Boiled Grape Must

Its worth mentioning that just like modern times there was an array of wine types in classical times and not just one "style". Consumer preferences also changed throughout time. For example in the late republic and early empire periods heavy and robust wines were fashionable. Later the more elegant and lighter wines from ibera and gaul became fashionable.

Your class would make a difference too. If you were a soldier or slave your drink was most likely a very watered down wine that had mostly vinegar in it. If you were wealthy you would have access to long-aged and concentrated syrupy dessert-style wines.

Also, see this thread:

http://www.reddit.com/r/AskHistorians/comments/22kbux/has_beer_always_tasted_pretty_much_how_it_tastes/