McGeechan said the success being enjoyed by Edinburgh Rugby and Glasgow Rugby in the Celtic League would continue when the two sides step onto the European stage this weekend.
"There is a real buzz about rugby in this country at the moment," he said.
"We have finally accepted professionalism across the board and we're seeing the benefits of this in the Celtic League. We have stepped up another level and the Scottish sides in the Heineken Cup are in the best shape they have ever been in.
"I'm sure they will make a big impact this season. And in the next two or three seasons, they'll make an even bigger impact as the benefits of professionalism kick in. There's also great support for both teams, as well as Borders, which is terrific to see."
McGeechan said men from the Southern Hemisphere were having a big impact on Scottish rugby. New Zealanders Tony Gilbert (Borders), Kiwi Searancke (Glasgow Rugby) and Edinburgh stars Todd Blackadder and Brendan Laney have been in the forefront of Scotland's Celtic League success.
"It's not so much a New Zealand style of play that they bring to the game, it's their attitude," said McGeechan. "They work hard and the benefits are showing throughout the teams.
"They are good role models for our players. Todd Blackadder is one of the most impressive men I've ever met - and not just because of what he does on the rugby field. He is an absolute goldmine for Scottish rugby."
McGeechan said the talent coming through the country's three professional sides was also good news for the national side.
"The likes of Edinburgh scrum-half Michael Blair might not be well known among European fans yet, but he will be. Glasgow's Calvin Howarth and Stuart Moffat are also in great form, and it's good to see some of the old hands like Alan Bulloch and Jon Steel playing well.
"And we all know what an outstanding rugby player Simon Taylor (Edinburgh) is, and I'm sure he'll be right in amongst things in the Heineken Cup."
English teams have contested Heineken Cup finals in each of the five previous seasons they have entered the tournament.
England head coach Clive Woodward said: "The 2003 Heineken Cup was officially launched on the last day of September and, like all international and club coaches, fans, media, sponsors and players, it's a tournament we all enjoy.
"To date the quality of rugby in the Heineken Cup has been of a very high standard and the finals will stay in the memory for a very long time.
"My old club Leicester Tigers has achieved a double in the competition, winning it in the last two years and is now going for a hat trick of wins. I wish them and all the other participating clubs the best of luck and I hope, as they do, that the 2003 tournament lives up to the expectations of everyone and continues to grow.
"I will be watching many of the games myself and look forward to what I'm sure will be a great spectacle and showcase for rugby union.
Wales coach Steve Hansen will be at The Gnoll on Friday night when Neath meet defending champions Leicester Tigers with New Zealander Hansen looking for the six Welsh clubs to build up confidence that will rub off on the national cause.
"The Heineken Cup provides another level of competition up from the normal and gives me and the Welsh coaching staff the opportunity to see and assess players at this higher standard," said the former Canterbury Crusaders coach.
"The Heineken Cup is the most important competition outside the Six Nations - the razzmatazz gets people really excited about the game. It provides the whole package to sell the game to the public.
"Selection is continually an on-going thing and this competition is the best thing in Europe - that has to make it hugely beneficial to people like myself. This gives us the chance to see players, be they on the fringe or established, and gauge current form.
"What I am hoping to see is good team and individual performances across the board and it would be nice to see the Welsh clubs do well in the Heineken Cup because they would then take that confidence with them into internationals." John Kirwan, the legendary All Black wing now coaching the Italian national team, said: "The Heineken Cup is a fantastic tournament for me - I want all our leading Italian teams playing in Europe.
"The Heineken Cup provides a far higher level of competition for our teams and that is fundamental to our development. It provides a yardstick for me to measure the potential of emerging players and the matches are extremely important for Italy.
"I will be going to as many matches as possible where there is a strong Italian interest.
"The tournament was a bit negative for us last season in the way of results but to me the Heineken Cup is like the Super 12 - the more we play these games the better we will get." Brian O'Brien, the Ireland team manager who knows the Heineken Cup inside out after his time with Munster, believes the tournament "has, since its inception, been a godsend to northern hemisphere rugby - and Irish rugby in particular.
"It has enhanced the level underneath international rugby and the tournament has become a flagship of all rugby supporters. It is a phenomenal competition.
"Because prior to the professional era, Irish provincial rugby was going downhill, you were lucky to get 300 spectators at provincial matches but now we get full houses at Thomond Park, Donnybrook and Ravenhill.
"The Heineken Cup has raised everyone's standards - and expectations - and that has been great for Irish rugby, from the top to the bottom of our game."
French coach Bernard Laporte said: "The Heineken Cup matches are played at a higher level than any of the domestic championships. That makes it very interesting to see how players develop under those circumstances - and the players who compete in the Heineken Cup say so themselves.
"It is important the French clubs do well in the Heineken Cup and success comes through good performances. There may be more good teams in England than there are in France but I'm not so sure the best French teams are far behind the best four or five English sides.
"A good start to the French clubs' European campaign would be a bonus ahead of the November international matches. I can't say which French clubs are more likely to do well in the Heineken this year - I hope they will all be successful - but it will be interesting to see how players such as the Biarritz half-back pairing, Dimitri Yashvilli and Julien Peyrelongue, perform at this level."